Annu. Rev. Entomol. 1990. 35:299-318

Copyright © 1990 by Annual Reviews Inc. All rights reserved

ARTHROPODS AND OTHER

INVERTEBRATES IN

CONSERVATION-TILLAGE

AGRICULTURE

Benjamin R. Stinner

Department of Entomology, Ohio State University, Ohio Agricultural Research and Development Center, Wooster, Ohio 44669

Garfield J. House

Department of Entumology, North Carolina State University, Raleigh, Nurth Carolina 27695

INTRODUCTION

For most of agriculture's history, soil tillage has been synonymous with growing crops. Tillage prepares seedbeds, incorporates organic material and fertilizer, and suppresses weeds and some diseases and insect pests (52, 131). Originally, tillage was mostly surface cultivation by hand or animal power with primitive implements. By the eighteenth and nineteenth centuries, the moldboard or turning plow enabled tillage at greater depths (144). This deep plowing loosens the soil considerably and mixes manure and other fertilizers throughout the soil. The moldboard plow inverts the top 20--25 cm of soil and buries plant debris, leaving a nearly bare soil surface. This technology became the most widely used form of tillage in mechanized agriculture (l08).

During the 1930s, severe soil erosion and "dust bowl" conditions in the North American Midwest spawned grave concern over agricultural practices, especially plowing and cultivation (14). In response to this crisis, the newly formed Soil Conservation Service implemented many soil-protecting mea­sures, including a land reserve program that removed severely erodible lands from crop production (15). In 1943, Edward Faulkner (44) published a short

299 0066-4170-90-0101-0299$02.00

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

300 STINNER & HOUSE

albeit widely read book, Plowman' s Folly, in which he questioned the necessity of plowing, from the perspective of environmental concerns and of plant productivity. Faulkner prophetically described many of the directions that reduced tillage agriculture is currently pursuing.

Herbicide introduction in the late 1940s and early 1950s provided an alternative to tillage and cultivation for weed suppression (8, 32). Subsequent experiments demonstrated the feasibility of crop production without plowing or tillage; this was termed no-tillage agriculture (130, 142). Reduced- and no-tillage agriculture have important implications for soil conservation: The accumulation of crop residues on soil surfaces as a result of minimal soil disturbance greatly protects soil from water and wind erosion (45, 56, 81). Motivated by support from conservation agencies and savings on reduced fuel and labor (tillage is a relatively energy expensive and time-consuming opera­tion), farmers gradually began to adopt reduced- and no-tillage practices, together referred to as conservation tillage, approximately 20 years ago. A recent survey of tillage practices in the United States showed that 32% of all cropland is managed with some form of conservation tillage (31). Within the next 25 years the majority of US cropland will likely be in conservation­tillage agriculture (91). Research and adoption of no-tillage and reduced­tillage agriculture has also occurred on a worldwide basis (47, 107, 82,105).

Conservation-Tillage Terminology

The great diversity of tillage operations and technology to accomplish soil manipulations has resulted in a variety of terms to describe tillage. For the purposes of this review, we use the following terminology: Conventional

tillage refers to moldboard plowing where soil is inverted prior to planting and produces a surface with little or no remaining plant residues. Reduced or minimum tillage embraces a range of mechanical operations using disks, chisels, sweeps and other implements to loosen the soil and still leave a relatively large amount of plant material on the surface. No-tillage is the extreme form of reduced tillage where essentially no soil manipulation is performed prior to planting. Seeds are deposited into narrow grooves cut using specialized planting equipment. Virtually all crop residues are left on the soil surface. Direct-drill and zero tillage are synonymous with no-tillage. Conservation tillage encompasses both reduced- and no-tillage farming. Strictly defined, conservation tillage entails leaving a minimum of 30% of the previous crop residues on the soil surface (52).

Ecological Conditions in Conservation Tillage

Tillage or the lack of it influences arthropods and other invertebrates in three major ways: mechanical disturbance, residue placement, and effects on weed communities (74). Plowing acts as a physical disturbance affecting the hori­zontal and vertical distributions of soil biota (Figure 1). In a general sense,

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

ARTHROPODS IN CONSERVATION TILLAGE 301

plowing should be viewed as a perturbation to soil invertebrate communities that occurs once to several times a year, depending upon management prac­tices. In conservation-tillage systems, litter and soil organic matter tend to concentrate near the soil surface (Figure 1). In conservation-tillage systems, crop debris and manures get incorporated into the soil, albeit slowly, through invertebrate activity. The litter layer is a very important factor in ameliorating soil temperature and moisture extremes (57), thus providing a more stable environment for soil- and litter-dwelling invertebrates. Changing the degree and type of tillage also affects density and community structure of weeds. For example, no-tillage management favors persistence of perennial over annual weed species (141). Because the ecology of many insects and other in­vertebrates is linked to weeds, tillage indirectly affects invertebrates through its influences on weed communities (136, 25).

These same mechanisms also influence the physical, chemical, and biologi­cal properties of soils. Briefly, lack of tillage preserves soil structure includ­

ing aggregate size and pore density and distribution, characteristics which contribute to water infiltration and retention (140, 127). As tillage is reduced, soil organic matter and nutrients tend to concentrate in the upper soil levels compared to conventionally plowed soils (18, 19, 58, 137). Conservation­tillage soils often have lower pH values at the surface (135). Microbial

populations are larger in the surface of no-tillage soils than in plowed soils (35, 90). Non-tilled conditions favor the development of fungal-based soil food webs in contrast to more bacterial-based detrital food webs in plowed soils (65, 68). These conditions are thought to effect more rapid decomposi­tion of organic materials and to favor greater nutrient mobility in conventional vs. conservation-tillage soils (72).

CONSERVATION TILLAGE IMPACT ON PESTS

Early Studies on Pests Influenced by Tillage Practices

Incorporation of crop residues by tillage destroys habitat for some pests; inverting soil exposes certain pest species to weather conditions, which can contribute to population suppression of these insect populations (1, 109). When conservation-tillage systems were first introduced, it was thought, a priori, that there would be an accompanying increase in pest severity, es­pecially with soil-inhabiting insects (54). Many of the early studies on pests associated with conservation-tillage systems in the United States dealt with com (Zea mays), reflecting the major effort that went into encouraging conservation-tillage practices for this crop (108).

Some of earliest research in the United States linking conservation tillage and pest incidence was reported from Ohio. Crop-seedling emergence and increased populations of soil-inhabiting pests were associated with no-tillage practices (100). Musick & Collins (101) found that adult northern com

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

Increased

Conservation Tillage Conventional Tillage

- ----

"." " ";"ti, �:§{�:: \: " : <. � .� � >:;.: .;;�.', ,. 0 � 0 .. () (::) .' () ." • 0. . • '", . 0 c::.. 00 f o� GOo 00

v _ _ - QC::; ()O .1700 .... /><> ••• Oa:,?·O��."o�'.o.0 "O�O,� 0: o·a. Q �� � o.Earthworm .... � ':'-1' :". .... . . ' . .... ... . c '- ' .

• �o:::�-o" •• �v 0 D��aO �o� -So vo. o:·��::·;���i�Y·e�: ��:;: �::;'�'�.��� .. (�.·o>�::< .. : )1> • .-�"ooo.o"OO O�ClPa��l?I�'.o-l" : . ' ,' , (\ , .Q , " .. ' " ". ' " ,� . CI

. . - . - · .0. - A .'0 � - ."., '··:;�yf;,:.J ,�:,:;';:"Ji�ii:i:�

000

Figure 1 Generalized illustration of soil profiles from conventional- and conservation-tillage systems (Cindy Gray, artist),

VJ o N

CIl

�

Z

� R<>

a c::: CIl tTl

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

ARTHROPODS IN CONSERVATION TILLAGE 303

rootworm beetles, Diabrotica longicornis, a major root-feeding pest of com, laid three to four times more eggs in no-tillage than in conventionally plowed

fields. Yet egg survival and subsequent larval damage to com roots were equal or significantly less in the no-tillage systems, indicating greater mortal­ity sources under no-tillage conditions. Armyworm populations, Pseudaletia unipuncta, and their damage to crops increased when com was planted directly into sod fields or with small grain cover crops such as rye and wheat. Adult moths of this pest oviposit on these grasses; herbicides kill the grasses, and then larval armyworms feed on com (102, lO4). Increased black cutworm (Agrotis ipsilon) incidence was reported from no-tillage com fields (lO3, 64). Slugs were documented as a serious problem in reduced-tillage fields, es­pecially during excessively wet growing conditions (103).

At Rothamsted, England, from 1964 to 1974, Edwards (38) reported that

the only pests to increase significantly when tillage was eliminated were wireworms and slugs. Wireworms were two to three times more abundant in direct drill fields during cropping with continuous cereals, or cereals follow­ing sod, than in plowed fields. During mild wet winters, slugs were a particular problem when oil seed rape was included in rotation sequences.

In Georgia, All & Gallaher (1) found that damage to seedling corn by the lesser cornstalk borer, Elasmopalpus lignosellus, was significantly greater in conventionally plowed than in no-tillage fields. They also reported that infestations of European com borer (Ostrinia nubilalis) populations were over twice as high (32.8%) in conventional tillage as in no-tillage treatments (15.3%). However, in the same study, damage to corn by the com earworm, Heliothis zea, was greater under no-tillage conditions. Studies on the southern com billbug, Sphenophorus callosus, indicated that this insect was one of the most severe pests feeding on no-tillage com in southeastern United States, particularly when nuts edge (Cyperus esculentus) and crabgrass (Digitaria sanguinalis) were present (2). Tillage had little if any influence on incidence of maize chlorotic dwarf, or maize dwarf mosaic diseases or its vector, the leafhopper Graminella nigrifrons (3).

More Recent Studies on Pests

The widespread adoption of conservation-tillage agriculture during the 1980s was accompanied by an increased interest in pest biology and management in these systems. The expanded use of conservation tillage for other row crops besides corn, forage crops and vegetables stimulated research on pest ecology in different cropping systems.

SOYBEANS Adoption of conservation tillage methods for growing soybeans and other crops has been motivated by many of the same reasons as for corn--decreasing the potential for soil erosion, reducing fuel and labor costs,

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

304 STINNER & HOUSE

and conserving moisture (79). Hammond (62) concluded that conservation­tillage farming practices have not resulted in an overall increase of in­vertebrate pests on soybeans. Rather, shifts have occurred in abundances and the relative economic importance of various phytophagous species.

Some of the first reports on soybean arthropods in conservation-tillage systems partitioned the arthropods into guilds. In Georgia, House & Stinner (63) observed greater species diversity of foliage arthropods in no-tillage than in conventionally plowed soybeans; they attributed this finding to increased structural diversity in soil litter layers and to higher weed density and diversity in the no-tillage systems. In another study, analysis of no-tillage soybean systems in relation to weed density and community composition revealed that more arthropod taxa inhabit weedy soybeans than weed-free soybeans, and higher arthropod diversity is found in broadleaf than in grass weeds (123).

In Kentucky, green cloverworm, Plathypena scabra, laid greater numbers of eggs in double-cropped, no-tillage soybean following wheat than in con­ventionally tilled soybeans (128). However, subsequent larval populations were lower in no-tillage soybeans, suggesting higher pest mortality in this system. The same study found a trend toward lower populations of foliage­feeding beetles in no-tillage treatments. Research in Louisiana indicated higher densities of green cloverworm in no-tillage compared with tilled soybeans (143). From an Ohio study comparing tillage practices in soybeans following winter rye crop, higher populations of green cloverworm were observed in no-tillage than in either disk or moldboard plow treatments during one year of a two-year study (129).

Considerable attention has been focused on seedcom maggots, Delia p/a­tura, in relation to conservation-tillage soybeans, particularly on how the ecology of this species is affected by cover-cropping treatments. The dipteran larvae feed on germinating seeds and frequently kill or deform seedlings. Decaying vegetation and high levels of organic matter may attract egg-laying flies and provide a rich habitat for developing larvae (55). Funderbuck et al (49) found higher populations of maggots in chisel-plowed (surface-tillage) treatments that had only partially buried plant residues than in either no-tillage or moldboard-plowed soils. Subsequent studies supported these findings when soybeans were planted after a winter cover crop of rye or a previous crop of alfalfa was only partially incorporated into the soil with shallow tillage. This positive influence on maggot populations was particularly evi­dent when the previous crop residue was green rather than dried or senescent when incorporated (59, 60). In a recent North Carolina study, D. platura populations were higher in conventional- than in no-tillage com following legume cover crops (G. J. House, A. Alzugara, unpublished data).

Other soybean pest species given attention in relation to conservation tillage include Heliothis (115, 134), Mexican bean beetle, Epilachna vari-

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

ARTHROPODS IN CONSERVATION TILLAGE 305

vestris (134), bean leaf beetle, Cerotoma trifurcata (143), and slugs (61). These studies have not indicated economically significant increases of pest damage with conservation tillage practices, with the exception of slugs in eastern portions of the US grain belt.

FORAGE CROPS To decrease soil erosion potential, attention has been di­rected towards establishing pasture and forage crops using conservation­tillage methods (97). Damage to seedlings by invertebrates was predicted to be a major obstacle to the adoption of reduced- and no-tillage planting of forage crops. In fact, damage by slugs (53, 27, 28), fIeahoppers (96), and crickets (116) has been associated with poor alfalfa, Medicago sativa, es­tablishment under conservation-tillage conditions.

Barney & Pass (13) compared foliage arthropod communities on no-tillage and conventionally planted alfalfa in Kentucky where they found that pest populations of alfalfa weevil, Hypera postica, clover root curculio, Sitona hispidula, and aphids did not increase under no-tillage treatment. Populations of potato leafhopper, Empoasca fabae, probably the most important pest of alfalfa in this region, were reduced in no-tillage treatments. The authors attributed this last finding to higher grass density among alfalfa in the no-tillage treatments. Other researchers have shown that grasses deter pop­ulations of potato leafhoppers (84).

Contributions to a 1986 International Symposium on Establishment of Forage Crops by Conservation Tillage (67) indicated that pest problems with conservation-tillage forage crops are frequent and more severe than damage encountered in row crops under conservation tillage. Still, forage crops harbor substantial populations of natural enemies (13) whose value should not be discounted and that merit further study.

CORN During the past decade, attention has been given to lepidopterous herbivores on corn in relation to conservation-tillage systems. The stalk borer, Papaipema nebris, serves as an example of a pest that has become more prevalent with the adoption of no-tillage corn, as a result of changes in weed distributions. This moth has a broad host-plant range and historically has been associated with damage to corn in limited areas along field edges where grasses are typically abundant (34). Adults oviposit in grass during late summer and early fall (89); the larvae emerge the following spring, and early instars inhabit grasses. Because grasses tend to be more abundant under no-tillage conditions and distributed throughout corn fields, stalk borer pop­ulation dynamics have been altered concomitantly. The larvae will typically move from grassy weeds to corn when herbicides are applied, and therefore areas within com fields can be damaged (136). Studies from Ohio (88), Iowa

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

306 STINNER & HOUSE

(11, 86), and Virgina (66) have examined consumption rates and movement patterns of the stalk borer in conjunction with no-tillage practices.

In a comparative assessment of soil and foliage arthropod communities after 20 years of conventional- (moldboard), reduced- (disked), and no-tillage corn cropping in Ohio, black cutworm damage was least in the conventional­tillage treatment. Damage to corn by both European corn borer and com rootworm was not significantly affected by tillage treatments (137).

COTTON Plowing and cultivation have been traditional methods used to reduce populations of the boll weevil, Anthonomus grandis, and Heliothis

spp. (51). Tillage reduces overwintering populations of weevils within cotton fields and restricts adults from building fat reserves prior to diapause (51). Tillage also is injurious to Heliothis, especially in the pupal stage. Significant injury to these pests can occur in plowed soil from heavy rains (69). Despite damaging influences of tillage on these pests, Gaylor & Foster (51) and Gaylor et al (50) reported that damage by these two species and Lygus spp. did not increase with the use of conservation-tillage systems in Alabama. Furthermore, these researchers have indicated that some of the cultural prac­tices associated with conservation-tillage cotton production, such as delayed planting with double-cropping systems, actually reduce boll weevil damage. In northern Alabama, variegated cutworm popUlations (Peridroma saucia) increased in conservation-tillage cotton. Damage severity to the cotton was dependent upon cover-cropping practices (50).

Pest Populations in Tropical Conservation Tillage

A review of insect responses to no-tillage management in Costa Rica con­cluded that no-tillage management of corn incurred appreciably less insect pest damage than did conventional plowing of com (124, 125). Others have reported that damage by the beetle Diahrotica halteutu was six times greater in plowed than in no-tillage corn; this difference was attributed to oviposition preference in the plowed treatment. Similarly, damage by the fall armyworm, Spodoptera !rugiperda, was much greater in plowed vs. no-tillage corn, as was damage by the heteropteran Cyrtomenus bergi and by Phyllophaga spp. (29, 124, 78, 30).

At the International Rice Research Institute in Manila, the Philippines, research on minimum- and no-tillage rice production indicates that there is greater abundance of foliage insects in conventional-tillage than in no- or zero-tillage legumes (77). Zero tillage and the resultant rice stubble mulch reduce populations of the leafhopper Amrarasca bigutulla, and of the bean fly Ophiomyia phaseoli. This pattern occurred because the insects have a strong predisposition to landing on bare soil, which in tum is thought to be related to

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

ARTHROPODS IN CONSERVATION TILLAGE 307

obstruction of long-wavelength radiation by the mulch and stubble on the zero-tillage treatments (92).

Overall Patterns of Pest Damage in Conservation Tillage

We surveyed 45 studies that documented influences of tillage or lack of it on invertebrate pests and their damage to crops; these studies represent data on 51 arthropod pest species from widely differing regions of the world. Twenty­eight percent of the species and their damage increased with decreasing tillage, 29% showed no significant influence of tillage, and 43% decreased with decreasing tillage. A previous review of 35 pests, considered in relation to conservation tillage estimated that damage to crops would increase with 24% of the species (80); this agrees approximately with our survey.

INFLUENCE OF CONSERVATION TILLAGE ON NATURAL ENEMIES

Soil-Inhabiting Macroarthopods

One of most frequent and widespread observations regarding arthropods in conservation tillage is the increase in soil- and litter-inhabiting predatory arthropods, especially ground beetles (Carabidae) and spiders, as tillage is decreased (4, 113, 132). A British study showed that carabid beetles in particular are important predators of cereal pests (40). Greater carabid beetle abundance was reported from conservation-tillage than from conventionally plowed soybeans in Georgia (70). On some sampling dates, carabid density in the conservation-tillage systems was as much as four times higher than in the conventional treatments. Also in Georgia, greater diversity of soil surface macroarthropods was reported in no-tillage than in conventionally plowed systems (20). In another study comparing no-tillage and conventional-tillage soybeans, a mean density of 17.6 carabid beetles per m2 was documented in no-tillage vs. 0.38 per m2 in plowed treatments (73). Tillage effects on spider populations were less marked, but spider density was higher in the no-tillage treatment, with the exception of onc sampling date. In northeastern Italy, Paoletti (107) recovered greater numbers of predatory beetles and spiders from pitfall traps in no-tillage and reduced-tillage than in conventionally plowed com systems. A similar trend was reported for com systems in Ohio after 20 years of continuous treatment (137).

To evaluate how these soil macroarthropods affect pest populations from different tillage systems, researchers in Ohio manipulated both macroarthro­pod predator and black cutworm prey populations in conventional and no­tillage com systems (21, 22). They found four times more com plants destroyed when predators were removed than when they were present in no-tillage treatments. In these studies, tillage significantly reduced both

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

308 STINNER & HOUSE

predator density and predation rates on cutworm larvae. The predatory taxa included carabid and staphylinid beetles, phalangids, lycosid spiders, and

ants. Across tillage treatments, cutworm damage to com was negatively correlated (,-2 = .90) with absolute density of predators. In cotton systems, removal of soil-dwelling predators from both conventional- and conservation­tillage systems significantly increased emergence of adult Heliothis moths (50). Attacks by ants on prepupa of Heliothis zea in no-tillage com were significantly more frequent than in plowed soils (85).

These soil- and litter-dwelling macro arthropods are, for the most part, generalist feeders. For example, carabid beetles are known to feed as carni­vores, herbivores (including weed seeds), and fungivores (16, 25, 112). Although the predatory macrofauna can be very important in reducing specific pest populations, much of these animals' food resources on a year-round basis

are provided by nonpest sources, including organisms in detrital food chains such as collembola (119, 117). Since conservation-tillage systems support greater densities of detrital feeding fauna and microflora involved in de­composition processes (65, 73), the linkages between predatory and detrital food webs deserve further attention.

Soil and Litter Microarthropods as Predators

Although less attention has been given to the predatory roles of microarthro­pods than to those of macroarthropods, some data and inferences should be emphasized. In particular, mites (Mesostigmata, Acarida and Prostigmata) and certain collembolan taxa are important predators of other arthropods and their eggs and of nematodes (146). Tillage can have significant influence on the abundance and distributions of these organisms in soils (43, 98). In one of the few quantitative studies on microarthropod predation in agroecosystems, Brust & House (24), working in North Carolina, found that the acarid mite Tyrophagous putrescentiae occurs in higher numbers in no-tillage than in conventional-tillage peanuts, and it is an effective egg predator of the south­ern com rootworm, Diabrotica undecimpunctata howardi, under no-tillage conditions. Based on observations and data from Ohio (D. A. McCartney, B. R. Stinner, unpublished data), we suspect that microarthropod predation is a significant overwintering mortality factor for Diabrotica in the midwestern United States as well. We predict that further study will provide additional evidence that predation by microarthropods and other mesofauna in conserva­tion tillage systems is an important biotic regulatory mechanism, directly and indirectly affecting pest population dynamics.

Foliage-Inhabiting Predators and Parasitoids in Conservation Tillage

In Georgia, a greater abundance of predatory foliage-inhabiting insects, mostly Coleoptera and Hemiptera, was found in no-tillage systems than in

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

ARTHROPODS IN CONSERVATION TILLAGE 309

conventional tillage, which was attributed in part to greater weed density in the former (71). Troxclair & Boethel (143) reported that the density of foliage-inhabiting, predacious hemiptera was higher on Louisiana no-tillage soybeans in some sites and lower in other locations, when compared to conventionally tilled systems. Troxclair & Boethel proposed that weed den­sity and species composition were not significant factors affecting foliage­inhabiting insects in their study. However, Hammond (62), citing the work of Altieri et al (6) and Shelton & Edwards (123), argued that weeds are impor­tant determinants of predator guild distribution and of abundance in con­servation-tillage soybean systems. Ferguson et al (46), finding numbers of predators more abundant in no-tillage vs. conventionally plowed soybeans, attributed this difference to planting date, row spacing, and previous crop stubble interacting with the tillage systems. Summarizing results of zero tillage in the tropics, van Rijn (145) also indicated that crop stubble, as well as weeds, contributes to maintenance of predator populations. House (76) re­

ported higher densities of soil arthropods, especially predators, in the root systems of weeds under no-tillage than under conventional-tillage manage­ment. House thought this indicated that certain weed species provide refugia for predators in no-tillage systems. Foster & Ruesink (48) showed that the black cutworm parasitoid Meteorus rubens lived longer, attacked more hosts, and reproduced more successfully when provided with flowering weed spe­cies-wild parsnip, wild mustard, chickweed, shepherds purse, and smart­weed-typically encountered in minimum-tillage corn fields.

DECOMPOSITION AND NUTRIENT CYCLING PROCESSES

Influence of Tillage on Decomposer Fauna

Numerous studies have documented the impacts of tillage and cultivation on soil invertebrates associated with decomposition processes (36, 65). Although as one would expect, specific effects vary with taxa and geographical loca­tion, tillage changes community composition, and popUlation distribution patterns and, in general, decreases the overall abundance of invertebrates involved in decomposition processes. Studies from a wide range of geograph­ical locations and soil types have demonstrated that overall tillage has a depressing effect on mite and collembolan populations, although a number of taxa are either neutrally or positively influenced by tillage (36, 37, 39, 73, 107, 122, 137). Earthworm densities also are generally decreased with tillage (73, 82), as are nematode numbers (133).

Roles of Fauna in Decomposition

Although the important roles of soil invertebrates in affecting the decomposi­tion of organic materials and cycling of nutrients have been well recognized

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

310 STINNER & HOUSE

for natural ecosystems for a considerable time (10, 33, 121), only more recently has this function been investigated in agricultural ecosystems (9).

House et al (72) and House & Stinner (74) hypothesized that invertebrate activity and the interaction of invertebrates with microflora are enhanced in conservation- and no-tillage soils, when these are compared to conventionally plowed soils. They proposed that the surface-maintained litter under con­servation-tillage management provides a continuous resource in space and time for many decomposer organisms. This litter stratum also should increase storage of nutrients in organic matter. Indeed, fungal and bacterial densities have been documented as increasing with decreasing tillage (12, 35). In a Colorado wheat agroecosystem, it has been determined that surface placement of straw litter in no-tillage systems affected microclimate and microbial communities to the extent that losses of soil organic matter and nutrients were minimal compared to buried litter in plowed soils (68).

Arthropods and other invertebrates affect plant residue decomposition di­rectly through ingestion, comminution, and redistribution of organic matter, and indirectly by influencing the dynamics of fungi and bacteria (121, 87, 99). In forest ecosystems, microarthropods contribute significantly to the decomposition rates or mass loss of litter (120, 17). During decomposition processes in forest and grassland litter, micro arthropods are reported to stimulate nitrogen cycling within litter by feeding on microflora, to increase mineralization rates of phosphorus, and to affect potassium and calcium dynamics very little or quite variably (120).

In a wide range of climatic conditions plant decay proceeds more rapidly in conventional-tillage than in reduced- and no-tillage systems (18, 72, 118). Because fungi tend to colonize surface-maintained plant residues more densely than they do buried residues (65, 68), and fungus-feeding arthropods typically are more concentrated in the upper soil-litter stratum of con­servation-tillage systems (93, 122), arthropod regulation of decomposition and of nutrient transformations should be greater in conservation- than in conventional-tillage agriculture. Decomposition in no-tillage practices re­portedly is more rapid, and nitrogen loss greater in litterbags that allow immigration of invertebrates than when the animals are excluded; these facts indicate that the microarthropods may play a significant role in nitrogen dynamics (75).

Earthworms play a major role in the breakdown of plant material in agricultural systems (87, 95). These animals also are important in affecting soil physical characteristics and distribution of organic matter (87). Since earthworm abundance and activity are much more evident in reduced- and no-tillage agriculture, the' relative roles of these animals in affecting de­composition and nutrient and plant growth processes generally is related inversely to the amount of tillage in agricultural practices (41).

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

ARTHROPODS IN CONSERVATION TILLAGE 311

TILLAGE IN RELATION TO OTHER AGRICULTURAL PRACTICES

Compared with other cultural practices such as cropping patterns and pesti­cide usage, tillage is a strong determinant of invertebrate distribution and abundance. Still, research has demonstrated that tillage interacts significantly with other agronomic practices to affect changes in invertebrate communities and the roles that the fauna play in agricultural ecosystems.

Specific cultural factors, interacting significantly with tillage to affect invertebrates, include mulching (26), inorganic fertilizer applications (106), the presence of leguminous plant species in minimum-tillage pasture (97) and row crop systems (83), crop planting date (46), spatial planting patterns

(143), cover crop management (63, 114, 129, 147) rotation pattern (148), and previous crop species (23).

Pesticide application can significantly impact invertebrates both directly and indirectly in conservation-tillage systems. Because of the problems associated with specific pest species in conservation-tillage farming, con­

siderable effort has been directed toward developing insecticide control mea­sures for these systems (5). Since activity of decomposer and predatory fauna is concentrated near the surface of reduced tillage soils, these animals are particularly sensitive both to fallout from foliar-applied toxicants and to surface applied pesticides (38). Brust et al (21) found that a soil-applied organophosphate insecticide suppressed soil arthropod predator activity more in no-tillage than in conventional-tillage treatments.

Herbicide applications in no-tillage systems reportedly reduced microar­thropod populations involved in litter decomposition (146), largely indirectly it is thought, because the herbicide decreased weed biomass and changed soil moisture and temperature conditions. Herbicide application can increase pest damage to crops by removing weeds as alternate hosts and driving the pests onto crops (88, 136). Although space does not allow a detailed review here, sufficient evidence leads us to conclude that many pesticides have nontarget effects and that these influences, although very variable, can interact with tillage systems to change the net impact of invertebrates as pests, natural enemies, and decomposers in agroecosystems.

CURRENT AND FUTURE DIRECTIONS

Conservation-tillage agriculture has been criticized for causing increased use of pesticides (91). The greater surface-water retention characteristics of con­servation-tillage systems have focused intensifying concern on the potential contribution of conservation tillage to the pollution of ground water resources with pesticides and fertilizer (94). For this and other environmental and

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

312 STINNER & HOUSE

economic reasons, considerable effort has been placed on developing con­servation-tillage systems that rely less on pesticides and inorganic sources of

plant nutrients (111, 139, 138). Current efforts to achieve the goal of lower-input conservation-tillage

agriculture are focusing on the role of multiple cropping in reducing the need for chemical weed control and inorganic fertilizer (111). Multiple-cropping includes the use of cover crops and rotation systems to increase organic matter, and nitrogen acquisition in the case of legumes, and interplanting to suppress weeds and diversify crop yields. The overall impact of multiple­cropping practices is to increase vegetation cover in time and space and to increase the structural and species diversity of cropping systems, thereby affecting habitat for invertebrates. Although extensive research has not yet been carried out, it has been shown that these practices can have significant influences on herbivorous (51), predacious (7, 23), and decomposer in­vertebrates (114).

Many argue that chemical and energy inputs to agricultural systems should be reduced to better achieve long-term economic viability and environmental quality (42, ItO). Conservation tillage in some form undoubtedly will be a part of this future. Research and farming will be challenged to expand the roles that invertebrates play, not only as pests and natural enemies, but as agents in the regulation of ecosystem processes of decomposition and nutrient cycling. We predict that in lower-input agricultural systems, the emphasis will shift toward this larger role that invertebrates can play in conservation­tillage agriculture.

ACKNOWLEDGMENTS

The authors thank John Blair, Ronald B. Hammond, David A. McCartney, Dan Pavuk, Foster Purrington, Deborah Stinner, and Athayde Tonhasca for reviewing the manuscript and offering insightful comments for its improve­ment. We thank C. Britton, and P. Sachariat for their help with the literature review, and Cindy Gray for the illustration.

Literature Cited

I. All, 1. N., Gallaher, R. N. 1976. Insect infestations in no-tillage com cropping systems. Ga. Agric. Res. 17:17-19

2. All, J. N., Jellum, M. D. 1977. Efficacy of insecticide-nematocides on Spheno­phorous callosus and phytophagous nematodes in field com. J. Ga. En­tomol. Soc. 12:291-97

3. All, J. N., Kuhn, C. W., Gallaher, R. N., Jellum, M. D., Hussey, R. S. 1977. Influence of no-tillage-cropping, carbo­furan, and hybrid resistance on dy-

namics of maize chlorotic dwarf and maize dwarf mosaic diseases of com. J. Econ. Entomol. 70:221-25

4. All, J. N. 1978. Insect relationships in no-tillage cropping. Proc. First Ann. SE No-Till Syst. Conf., Univ. Ga. Spec. Publ. 5, pp. 17-19

5. All, J. N., Musick, J. N. 1986. Manage­ment of vertebrate and invertebrate pests. See Ref. 131, pp. 347-87

6. Altieri, M. A., Todd, J. W . , Hanser, E. W . , Patterson, M., Buchanan, G. A.,

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

ARTHROPODS IN CONSERVATION TILLAGE 313

Walker, R. H. 1981. Some effects of weed management and row spacing on insect abundance in soybean fields. Prot. Ecol. 3:339-43

7. Altieri, M. A., Wilson, R. C., Schmidt, L. L. 1985. The effects of living mulches and weed cover on the dyna­mics of foliage-and soil-arthropod communities in three crop systems. Crop Prot. 4:201-13

8. Anderson,1. C., Wolf, D. E. 1947. Pre­emergence control of weeds in com with 2, 4-0 1. Am. Soc. Agron. 39:341-42

9. Anderson, 1. M. 1988. The role of soil fauna in agricultural systems. In Recent Advances in Nitrogen Cycling in Agri­cultural Systems, ed. J. R. Wilson, pp. 89-1 1 2 . London: CAB Int.

10 . Anderson, J. M., Ineson, P. 1984. In­teractions between microorganisms and soil invertebrates in nutrient flux path­ways of forest ecosystems. In In­vertebrate-Microbial Interactions. ed. J. M. Anderson, A. D. Raynor, L. W. Walton, pp. 59-88. Cambridge: Cam­bridge Univ. Press

1 1 . Bailey, W. c., Pedigo, L. P. 1986. Damage and yield loss induced by stalk borer (Lepidoptera: Noctuidae) in field com. 1. Econ. Entomol. 79:233-37

1 2 . Barber, D. A., Standell, C. J. 1977. Preliminary observations on the effects of direct drilling on the microbial activ­ity of soil. Agric. Res. COW1. Letcombe Lab. Ann. Rep. 1976:58-60

1 3 . Barney, R. I., Pass, B. C. 1 987. In­fluence of no-tillage planting on foliage­inhabiting arthropods of alfalfa in Ken­tucky. J. Econ. Entomol. 80:1288-90

14 . Bennett, A. A. 1 935. Facing the erosion problem. Science 81:32 1-26

1 5 . Bennett, H. H. 1939. Soil Conservation. New York: McGraw-Hill

1 6 . Best, R. L., Beegle, C. C. 1 977. Food preferences of five species of carabids commonly found in Iowa cornfields. En­viron. En/omol. 6:9-12

1 7 . Blair, I. M., Crossley, D. A. Jr. 1988. Litter decomposition, nitrogen dynamics and litter microarthropods in a Southern Appalachian hardwood forest 8 years following clearcutting. 1. Appl. Ecot. 25:683-98

1 8 . Blevins, R. L., Smith, M. S., Thomas, G. W., Frye. 1983. Changes in soil properties after 1 0 years of no-tillage and conventionally tilled com. Soil Til­lage Res. 3:135-46

1 9 . Blevins, R. L., Smith, M. S., Thomas, G. W. 1984. Changes in soil properties under no-tillage. In No-Tillage Agricul­ture, ed. R. E. Phillips, S. H. Phillips,

pp. 190--230. New York: Van Nostrand Reinhold

20. Blumberg, A. Y., Crossley, D. A. Ir. 1982. Comparison of soil surface arthro­pod populations in conventional tillage, no-tillage and old field systems. Agro­Ecosystems 8:247-53

21. Brust, G. E., Stinner, B. R., McCart­ney, D. A. 1985. Tillage and soil insecticide effects on predator-black cut­worm (Lepidoptera:Noctuidae) in­teractions in com agroecosystems. 1. Econ. Entomol. 78:1389-92

22. Brust, G. E., Stinner, B. R., McCart­ney, D. A. 1986. Predator activity and predation in com agroecosystems. En­viron. Entomol. 15: 1 0 1 7-21

23. Brust, G. E., Stinner, B. R., McCart­ney, D. A. 1986. Predation by soil in­habiting arthropuds in intercrupped and monoculture agroecosystems. Agric. Ecosvstems Environ. 18:145-54

24. Brusi, G. E., House, G. J. 1988. A study of Tyrophagus putrescentiae (Acari: Acaridae) as a facuitative pred­ator of southern com rootworm eggs. Exp. Appl. Acarot. 4:335-44

25 . Brust, G. E., House, G. J. 1988. Weed seed destruction by arthropods and ro­dents in low-input soybean agroecosys­terns. Am. J. Altern. Agric. 3 : 1 9-25

26. Burton, R. L., Jones, O. R., Burd, J. D., Wicks, G. L., Krenzer, E. G. Jr. 1987. Damage by green bug (Homop­tera: Aphididac) to grain sorghum as affected by tillage, surface residues, and canopy. J. Econ. Entomol. 80:792-98

27. Byers, R. A., Bierlein, D. L. 1984. Continuous alfalfa: invertebrate pests during establishment. J. Econ. Entomol. 77: 1 5 00--3

28. Byers, R. A., Templeton, J. C. 1988. Effects on sowing date, placement of seed, vegetation suppression, slugs and insects upon establishment of no-till alfalfa in orchardgrass sod. Grass F or­age Sci. 43:279-89

29. Carballo, V. M. 1979. Incidencia de plages en maiz (Zea mays L.) bajo di­

ferentes sistemas de manejos de male­zas. Tesis Ing. Agro. Universidad, Cen­tro Univ. del Attantico. Guapiles, Costa Rica. 89 pp.

30. Carballo, V. M. 1982. Manejo del suelo rastrojo y plagas-interacciones y eJecto sobre el maiz (Zea mays L.). Tesis Mg. Sc. Univ. de Costa Rica/Centro Agron. Trop. de Investigacion y Ensenanza. Turrialba, Costa Rica. 94 pp.

3 1 . Conservation Technology Information Center (CTIC). 1988 . Annual Survey Statistics. West Lafayette, Indiana.

32. Crafts, A. S., Harvey, W. A. 1949.

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

314 STINNER & HOUSE

Weed Control. Adv. Agron. 1:289-320

33. Crossley, D. A. Jr. 1977. The roles of terrestrial saprophagous arthropods in forest soils. Current status of concepts. In The Role of Arthropods in Forest Ecosystems, ed. W. J. Mattson, pp. 49-56. New York: Springer-Verlag.

34. Decker, G. C. 1931. The biology of the stalk borer, Papaipema nebris (Gn.); Iowa State Agric. Res. Bull. 143

35. Doran, J. W. 1980. Microbial changes associated with residue management with reduced tillage. Soil Sci. Soc. Am. J. 44:518-24

36. Edwards, C. A., Lofty, J. R. 1969. The influence of agricultural practices on soil micro-arthropod populations. In The Soil Ecosystem, ed. J. G. Sheals, pp. 237-248. London: Pubis. Syst. Assoc.

37. Edwards, C. A. 1975. Effects of direct drilling on the soil fauna. Outlook Agric. 8:243-44

38. Edwards, C. A., Thompson, A. R. 1975. Pesticides and soil fauna. Ann. App/. BioI. 80:1-79

39. Edwards, C. A., Lofty, J. R. 1978. The influence of arthropods and earthworms upon root growth of direct drilled cere­als. J. Appl. Eco!. 15:789-95

40. Edwards, C. A., Sunderland, K. D., George, K. S. 1979. Studies on polyph­agous predators of cereal aphids. J. Appl. Ecol. 16:811-23

41. Edwards, C. A., Lofty, J. R. 1980. Effects of earthworm inoculation upon the root growth of direct drilled cereals. J. Appl. Eeol. 17:533-43

42. Edwards, C. A. 1988. The concept of integrated systems in lower input! sustainable agriculture. Am. 1. Altern. Agric. 2:1 48-52

43. Farrar, F. P., Crossley, D. A. Jf. 1983. Detection of soil microarthropod aggregations in soybean fields, using a modified Tullgren extractor. Environ. Entomol. 12: 1303-09

44. Faulkner, E. 1943. Plowman's Folly. Tulsa, Okla.: Univ. Okla. Press

45. Fenster, C. R. 1970. Conservation til­lage in the Northern Plains. J. Soil Water Conserv. 32:37-42

46. Ferguson, H. J., McPherson, R. M., Allen, W. A. 1984. Effect of four soy­bean cropping systems on the abundance of foliage-inhabiting insect predators. Environ. Entomol. 13:1105-12

47. Fleige, H., Baeumer, K. 1974. Effect of zero tillage on organic carbon and total nitrogen, and their distributions in dif­ferent N-fractions in loess'ial soil. Agro­Ecosystems 1: 19-29

48. Foster, M. A., Ruesink, W. G. 1984.

Influence of flowering weeds associated with reduced tillage in com: a black cut­worm (Lepidoptera:Noctuidae) para­sitoid, Meteorus rubens (Nees von Es­enbeck). Environ. Entomol. 13:664-68

49. Funderburk, J. E., Pedigo, L. P., Berry, E. C. 1983. Seedcorn maggot (Dip­tera:Anthomyiidae) emergence in con­ventional and reduced-tillage soybean systems in Iowa. J. Econ. Entomol. 76:131-34

50. Gaylor, M. J., Fleischer, S. J., Muehleisen, D. P., Edelson, 1. V. 1984. Insect populations in cotton produced under conservation tillage. J. Soil Water Conserv. 39:61-64

51. Gaylor, M. J., Foster, M. A. 1987. Cot­ton pest management in the southeastern United States as influenced by conserva­tion tillage practices. See Ref. 75, pp. 29-34

52. Gebhardt, M. R., Daniel, T. C., Schweizer, E. E., Allmaras, R. R. 1985. Conservation tillage. Science 230:625-30

53. Grant, J. F., Yeargan, K. V., Pass, B. C., Parr, J. C. 1982. Invertebrate organ­isms associated with alfalfa seedling loss in complete-tillage and no-tillage plant­ings. J. Econ. EntomoI. 75:822-26

54. Gregory, W. W. 1974. No-tillage corn pests of Kentucky. A five year study. In Proc. No-Tillage Res. Conj., pp. 46---58. Lexington: U niv. Kentucky

55. Gregory, W. W., Musick, G. J. 1976. Insect management in reduced tillage systems. Bull. Entomol. Soc. Am. 22:302-4

56. Griffith, D. R., Mannering, J. V., Mol­denhauer, W. C. 1977. Conservation til­lage in the eastern com belt. J. Soil Water Conserv. 32:20-28

57. Griffith, D. R., Mannering, J. V., Box, J. E. 1986. Soil and moisture manage­ment with reduced tillage. See Ref. 131, pp. 19-57

58. Groffman, P. M., Hendrix, P. F., Crossley, D. A. If. 1987. Nitrogen dynamics in conventional and no-tillage agroecosystems with inorganiC fertilizer or legume nitrogen inputs. Plant Soil 97:315-32

59. Hammond, R. B., Jeffers, D. L. 1983. Adult seedcorn maggots in soybeans re­lay intercropped into winter wheat. En­viron. Entomol. 12:1487-88

60. Hammond, R. B. 1984. Effects of rye cover crop management on seedcorn maggot popUlations in soybeans. En­viron. Entomol. 13:1302-5

61. Hammond, R. B. 1985. Slugs as a new pest of soybeans. J. Kans. Entomol. Soc. 58:364-66

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

ARTHROPODS IN CONSERVATION TILLAGE 315

62. Hammond, R. B. 1987. Pest manage­ment in reduced tillage soybean crop­ping systems. See Ref. 75, pp. 19-28

63. Hammond, R . B. , Stinner, B . R. 1987. Seedcorn maggots (Diptera:Antho­myiidae) and slugs in conservation til­lage systems in Ohio. J. Econ. Entomol. 80:680-84

64. Harrison, F. P . , Bean, R. A . , Qaiviyy, O. J. 1980. No-till culture of sweetcorn in Maryland with references to insect pests. J. £Con. Entomol. 73:363--65

65 . Hendrix, P. F. , Parmalee, R. W. , Cross­ley, D. A. Jr. , Coleman, D. c. , Odum, E. P . , Groffman, P. M. 1986. Detritus food webs in conventional and no-tillage agroecosystems. BioScience 36:374-80

66. Highland, H. B . , Roberts , J. E. 1987. Feeding preferences and consumption rates of stalk borer (Lepidoptera:Noc­tuidae) larvae using plants found in no­till corn. Environ. Entomol. 16: 1 235-40

67. Hill, R. R., Clements, R. 0. , Hower, A . , Jordan, T . , Zeiders, K . , eds. 1 986. Proc. Int. Symp. Establ. Forage Crops by Conservation-Tillage: Pest Manage­ment. University Park, Penn. : Penn. State Univ.

68. Holland, E. A. , Coleman, D. C. 1987. Litter placement effects on microbial and organic matter dynamics in an agroecosystem. Ecology 68:425-33

69. Hopkins, A. R . , Taft, H. M . , James, W. 1972. Comparison of mechanical cultivation and herbicides on emergence of bollworms and tobacco budworms. J. Econ . Entomol. 65:870-72

70. House, G. J. , All , J. N. 198 1 . Carabid beetles in soybean agroecosystems. En­viron. Entomol. 10: 1 94-96

7 1 . House, G. J. , Stinner, B . R. 1983. Arthropods in no-tillage soybean agroecosystems: Community composi­tion and ecosystem interactions. En­viron. Mgmt. 7:23-28

72. House, G. J. , Stinner, B. R., Crossley, D. A. Jr. , Odum, E. P. , Langdale, G. W. 1984. Nitrogen cycling in con­ventional and no-tillage agroecosystems in the Southern Piedmont. J. Soil Water Conserv . 39:194-200

73. House, G. J . , Parmalee, R. W. 1985. Comparison of soil arthropods and earth­worms from conventional and no-tillage agroecosystems. Soil Tillage Res. 5 :35 1-60

74. House, G. J. , Stinner, R . E. 1987. De­composition of plant residues in no­tillage agroecosystems: Influence of lit­terbag mesh size and soil arthropods. Pediobiologia 30:35 1-60

75. House, O. J. , Stinner, B. R . , eds. 1987. Arthropods in Conservation Tillage Sys-

tems, ESA Misc. Publ. No. 65. College Park, Md: Entomo!. Soc. Am.

76. House, G. J. 1989. Ecological in­teractions in low-input no-tillage agroecosystems. In Ecology and En­vironmental Issues in Agriculture, ed. M. G. Paoletti. Amsterdam: Elsevier. In press

77. International Rice Research Institute. 1 978. Annual report Jor 1977. Los Banos, Phillipines

78. Jiminez. T. 1 98 1 . Desempeno de siste­mas de cultivos con maiz, Jrijol comun y Jrijolllima, endos tipos de laboreo del svelo y dos niveles de Jerrilizacion con nitrogeno. Tcsis Mao. Sc. Univ. de Cos­ta Rica. Turrialba, Costa Rica: Centro Agron. Trop. de Investigacion y En­senanza

79. King. A. D. 1 983. Progress in no-till. J. Soil Water Conserv. 38: 160-61

80. Kuhlman, D. E . , Steffy, K. L. 1982. Insect control in no-till corn. In Proc. 37th Ann. Corn and Sorghum Res. Con/. , pp. 1 18-47. Wash. DC: Am. Seed Trade Assoc.

8 1 . Lal, R. 1986. Soil surface management in the tropics for intensive land use and high and sustained production. Adv. Agron. 5:2-109

82. Lal , R. 1988. Effects of macrofauna on soil properties in tropical ecosystems. In Biological Interactions in Soil, ed. C. A. Edwards, B. R. Stinner, D. H. Stinner, S. C. Rabatin, pp. 88-101 . Amsterdam: Elsevier

83. Lambert, J. D . , Amason, J. T. , Senatos, A . , Philogene, B. J. , Faris, M. A. 1987. Role of intercropped red clover in in­hibiting European corn borer (lepidop­tera: Pyralidae) damage to corn in East­ern Ontario. J. Econ. Entomol. 80: 1 192-96

84. Lamp, W. O., Barney, R. J. , Armbrust, E. J. , Kapusta, G. 1984. Selective weed control in spring-planted alfalfa: effect on leafhoppers and planthoppers (Homoptera:Auchenorrhyncha), with emphasis on potato leafhopper, Empoas­ca Jabae. Entomol. Exp. Appl. 36: 1 25-3 1

85. Landis, D. A. , Bradley, J . R. Jr. , Gould, F . 1987. Behavior and survival of Heliothis zea (Lepidoptera:Noc­tuidae) prepupae in no-tillage and con­ventional-tillage corn. Environ. Ento­mol. 16:94-99

86. Lasack, P. M . , Pedigo, L. P. 1986. Movement of stalk borer larvae (Lepi­doptera: Noctuidae) from noncrop areas in com. J. Econ. Entomol. 79: 1697-1 702

87. Lee , K. E. 1985. Earthworms: Their

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

316 STINNER & HOUSE

Ecology and Relationship with Soils and Land Use. Sidney: Academic

88. Levine, E. , Clement, S. L . , McCartney, D. A. 198 1 . Agronomic practices in­fluence black cutworm damage on com. Ohio Rep. 66:29-30

89. Levine, E. 1 985. Oviposition by the stalk borer, Papaipema nebris (Lepidop­tera:Noctuidae) on weeds, plant debris and cover crops in cage tests. J. Econ. Entomol. 78:65-68

90. Linn, D. M . , Doran, J. W. 1984. Aerobic and anaerobic microbial activity in no-till and plowed soils. Soil Sci. Soc. A m . J. 45:794-99

9 1 . Little, C. E. 1 987. Green Fields Forev­er. Washington, DC: Island Press

92. Litsinger, J. A . , Ruhendi. 1 984. Rice stubble and straw mulch suppression of preflowering insect pests of cowpeas sown after puddled rice. Environ. En­tomol. 1 3 :509-14

93. Loring, S . J. , Snider, R. J . , Robertson, L. S. 1 98 1 . The effects of three tillage practices on Collembola and Acarina populations. Pediobiologia 22: 1 72-S4

94. Logan, T. J., Davidson, J. M . , Baker, J . L . , Overcash, M . R. , eds. 1 987. Effects of Conservation Tillage on Groundwater Quality. Chelsea, Mich: Lewis

95. MacKay, A. D . , Kladivko, E. J. 1985. Earthworms and rate of breakdown of soybean and maize residues in soil. Soil Bioi. Biochem. 1 7:85 1-57

96. Managan, R. L . , Byers, R. A. 1987. Evaluation of Halticus bractatus as a probable pest of minimum-tillage legume establishment. Melsheimer En­tomol. Ser. 37:25-3 1

97. Managan, R. L. , Byers, R. A . , Wutz, A . , Templeton, W. C. Jr. 1982. Host plant associations of insects collected in swards with and without legumes seeded by minimum tillage. Environ. Entomol. 1 1 :255-60

98. Moore, J . c. , Snider, R . J. , Robertson, L. S. 1 984. Effects of different manage­ment systems on Collembola and Acar­ina in com production systems. Pediobiologia 26:143-52

99. Moore, J. C . , Walter, D. E. , Hunt, H . W . 1988. Arthropod regulation o f mi­cro- and mesobiota in below-ground de­trital food webs. Annu. Rev. Entomol. 73:419-39

1 00. Musick, G. J. 1970. Insect problems associated with no-tillage. In Proc. N. E. No-Tillage Con/. , pp. 44-59. Albany, NY: Chevron Chern. Co.

1 0 1 . Musick, O. J. , Collins, D. L. 1 97 1 . Northern com rootworm affected by til­lage. Ohio Rep. 56:88-9 1

102. Musick, O. J. 1973. Control of army­worm in no-tillage com. Ohio Rep. 58:42-45

103. Musick, O. J . , Petty , H . B . 1973 . Insect control in conservation tillage systems. In Conservation Tillage: The Pro­ceedings of National Conference. An­keny, Iowa: Soil Conserv . Soc. Am.

1 04. Musick, O. J . , Suttle, P. J . 1973 . Suppression of armyworm damage to no-tillage com with granular carbofuran. J. Econ. Entomol. 66:735-37

105. Muzzilli, O. 1 98 1 . Manejo da fertili­dade do solo. Fundacao Inst. Agron. de Parana, Parana, Brazil: Plantio directo no estado do Parana

106. Nakamura, Y. 1988. The effect of soil management on the soil faunal makeup of a cropped Andosol in central Japan. Soil Til/age Res. 12: 1 77-86

1 07 . Paoletti, M. G. 1987. Soil tillage, soil predator dynamics, control of cultivated plant pests. In Soil Fauna and Soil Fertility, ed. B. R. Stringanova, pp. 4 1 7-22. Moscow: Nauka

l OS. Phillips, S. H . 1 984. Introduction to no­tillage agriculture. See Ref. 19, pp. 1-10

109. Pike , K . S . , Glazer, M . 1982. Strip ro­tary tillage: a management method for reducing Fumibotys fumalis (Lepidop­tera: Pyralidae) in peppermint. J. Econ. Enramal. 75: 1 136-39

1 10 . Poincelot, R. P. 1986. Towards a Sus­tainable Agriculture. Westport, Conn: AVI

1 1 1 . Power, J. F. 1987. The Role of Legumes in Conservation Tillage Systems. An­keny, Iowa: Soil Conserv. Soc. Am.

1 1 2. Rabatin, S . C . , Stinner, B. R . 1988. Indirect effects of interactions between V AM fungi and soil-inhabiting in­vertebrates on plant processes. See Ref. 82, pp. 135-46

1 1 3 . Raney, H . 1974. Insects in no-till soy­beans. See Ref. 54

1 14. Ricker!, D. H . , Gordon, W. B . , Curl, E. A., Touchton, J . T. 1988. Winter legume and tillage effects on cotton growth and soil ecology. Soil Tillage Res. 1 \ :63-71

1 1 5 . Roach, S. H. 1 98 1 . Emergence of over­wintered Heliothis spp. moths from three different tillage systems. Environ. Entomol. 10: 8 1 7- 1 8

1 1 6. Rogers, D . D . , Chamblee, D. S . , Muel­ler, J. P . , Campbell, W. V. 1985. Fall no-till seeding of alfalfa into tall fescue as influenced by time of seeding and grass and insect suppression. Agron. J. 77: 1 50-57

1 17 . Ruhendi, Litsinger, J. A. 1982. Effect

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

ARTHROPODS IN CONSERVATION TILLAGE 317

of rice stubble and tillage methods on the preflowering insect pests of grain legumes. In Rep. Workshop on Crop­ping Systems Research in Asia. ed. W. G . Rockwood, G. Argosino, pp. 85-98. Los Banos, PhiIIipines: Int. Rice Inst.

1 1 8 . Sain, P. Broadbent, F. E. 1 977. De­composition of rice straw in soils as affected by some management factors. 1. Environ. Qual. 6:96-100

1 1 9 . Schaller, F. 1 968. Soil Animals. Ann Arbor, Mich: Univ . Mich. Press

1 20. Seastedt, T. R. 1984. The role of micro­arthropods in decomposition and mineralization processes. Annu. Rev. Entomol. 29:25-46

1 2 1 . Seastedt, T. R . , Crossley, D. A. Jr. 1 984. The influence of arthropods on ecosystems. BioScience 34: 157-61

1 22. Shams. M. N . , Snider, R . J . , Robert­son, L. S . 1 98 1 . Preliminary investiga­tion on the effects of no-till com produc­tion methods on specific soil mesofauna populations. Commerc. Soil Sci. Plant Analysis. 1 2 : 1 79-88

1 2 3 . Shelton, M. D . , Edwards, C. R. 1 983. Effects of weeds on the diversity and abundance of insects in soybeans. En­viron. Entomo!. 1 2:296-98

1 24. Shenk, M . , Carballo, M . , Saunders, J . 1 980. Interacciones entre sistemas de manipvlacion de malezas y combate de plagas en maiz. In Reunion Anval del Programa Cooperativo Centroamerica­no para el Mejoramiento de Cultivos Alimentidos. Guatemala: Guatemala, Resumenes

1 25. Shenk, M . . Saunders, J. L. 1 984. Vegetation management systems and in­sect responses in the humid tropics of Costa Rica. Trop . Pest Mgmt . 30: 186-93

1 26. Deleted in proof 127. Shipitalo, M. J . , Protz, R. 1 987. Com­

parison of morphology and porosity of a soil under conventional and zero tillage. Can. J. Soil Sci. 67:445-56

1 28. Sioderbeck, P. E . , Yeargen, K. V . 1 983. Green cIoverworm (Lepidoptera: Noctuidae) populations in conventional and double-cropped, no-till soybeans. 1. Econ. Entomol. 76:785-91

1 29. Smith, A. W . , Hammond, R. B . , Stin­ner, B . R . 1 988. Influence of rye-cover crop management on soybean foliage arthropods. Environ. Entomol. 17 : 1 09-14

1 30. Sprague, M. A. 1952. The substitution of chemicals for tillage in pasture reno­vation. Agron. J. 44:405-9

1 3 1 . Sprague, M. A . , Triplett, G. B . , eds.

1 986. No-Tillage and Surface-Tillage Agriculture. New York: Wiley. 467 pp.

1 32. Stassart, P. , Gregoire-Wibo, C. 1 983. Influence chi travail dusol sur les pop­ulations de carabides en grande cirttine, resultants preliminaires. Meded. Fac. Landbouwwet. Rijksuniv. Gent 48:465-74

133. Stinner, B . R . , Crossley, D. A. Jr. 1 982. Nematodes in no-tillage agroecosystems. In Nematodes in Eco­systems, ed. D. Freckman, pp. Austin, Tex: Univ. Texas Press

1 34. Stinner, R. E . , Reguiere, J . , Wilson, K. 1982. Differential effects of agroecosys­tern structure on dynamics of three soy­bean herbivores. Environ. Entomol. 1 1 :538-43

135 . Stinner, B . R . , Hoyt, G. D . , Todd, R . L . 1 983. Changcs i n soil chcmical prop­erties following a 12-year fallow: a 2-year comparison of conventional tillage and no-tillage agroecosystems. Soil Til­lage Res_ 3:277-90

1 36. Stinner. B . R . , McCartney, D. A . , Rubink, W. A. 1984. Some observa­tions on ecology of the stalk borer (Papaipema nebris (GN): Noctuidae) in no-tillage com agroecosystems. J. Ga. Entomol. Soc. 1 9:229-34

1 37 . Stinner, B. R . , McCartney, D. A . , Van Doren, D. M. Jr. 1 988. Soil and foliage arthropod communities in conventional , reduced and no-tillage corn (Maize, Zea mays L.) systems: a comparison after 20 years of continuous cropping. Soil Til­lage Res. 1 1 : 147-58

138. Stinner, B . R . , Blair, J . M . 1989 . Eco­logical and agronomic characteristics of innovative cropping systems for sustain­able agriculture. In Sustainable Agri­cultural Systems. ed. C. A. Edwards , N . Creamer. Ankeny, Iowa: Soil Conserv. Soc. Am. In press

1 39. Stinner, B. R . , House, G. J. 1 989. The search for sustainable agroecosystems. J. Soil Water Conserv. 44: 1 1 1- 1 6

140. Thomas, G. W. 1986. Mineral nutrient and fertilizer placement. See Ref. 1 3 1 , pp. 93- 1 1 6

1 4 1 . Triplett, G . B . Jr. , LytIe, G. D . 1 972_ Control and ecology of weeds in con­tinuous com grown without tillage. Weed Sci. 20:453-57

1 42 . Triplett, G. B . , Van Doren, D. M . 1 977. Agriculture without tillage. Sci.

Am. 236:28-33 143. Troxclair, N. N. Jr. , Boethel , D. J .

1984. The influence of tillage practices and row spacing on soybean insect pop­ulations in Louisiana. J. Econ. Enlomol. 7 7 : 1 5 71-79

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.

318 STINNER & HOUSE

144. Tull, Jethro. 1 733. Horse Hoeing Hus­bandry. London.

145. van Rijn, P. J. 1 98 1 . Pests and their control in no-tillage in the tropics. In No-Tillage Crop Production in the Trop­ics. ed. I . O. Akobundu, A. E. Deutsch, pp. 86-10 1 . Amsterdam

146. Wallwork. J. A. 1970. Ecology of Soil Animals. London: McGraw-Hili

147. Worsham, A. D. 1984. Crop residues kill weeds: allelopathy at work with wheat and rye. Crops Soils 37: 1 8-20

148. Zehnder, G. W., Linduska, J. 1. 1987.

Influence of conservation tillage prac­tices on populations of Colorado potato beetle (Coleoptera: Chrysomelidae) in rotated and nonrotated tomato fields. Environ. Entomol. 16:1 35-39

Ann

u. R

ev. E

ntom

ol. 1

990.

35:2

99-3

18. D

ownl

oade

d fr

om w

ww

.ann

ualr

evie

ws.

org

by O

pen

Uni

vers

ity o

n 05

/02/

13. F

or p

erso

nal u

se o

nly.