By Kelli Dugan. They eat. They die. The average one-year life span of the eastern lubber might seem lackluster, but the distinctive black grasshopper relatives make quite a splash as they gorge their way in locust-like clouds across the Southeast. These diverse food plants represented nine plant families. In southeastern Wyoming Platte County along a gravel road in Whalen Canyon , nymphs and adults were observed to feed mainly on common sunflower.
Young nymphs attacked seedling plants, which at the time of observation were 3 to 6 inches tall. To feed, the nymphs climbed the plant, adjusted their bodies, and fed at the edges of leaves, eating into the leaf and creating deep gouges.
A third instar was observed to feed on the leaf of a 3-inch plant for three minutes. Later in the season, adults attacked the leaves, buds, and flowers of plants now 17 to 32 inches tall. Two adults one a female, the other unsexed were observed feeding into the sides and developing seeds of green heads.
Each fed for 16 minutes before completing its meal. Populations inhabiting two sites near Boulder, Colorado were associated with the sunflower, Helianthus pumilus. This leads one to suspect that among the 13 species of Helianthus distributed on the Great Plains, other members of the genus may serve as host plants and support isolated populations.
A suspected host species is the prairie sunflower, Helianthus petiolaris, specimens of which were observed to have been defoliated by a small population of the plains lubber grasshopper inhabiting a roadside in Platte County, Wyoming. A study of the foraging behavior of the plains lubber grasshopper in a southeastern Arizona site confirmed its highly polyphagus behavior.
Adults were observed to feed on 21 species of plants belonging to 15 plant families. Feeding bouts were short with the majority lasting less than two minutes, indicating that few suitable food items were present.
Preferred plants included Boerhaavia coccinea, Hymenothrix wislizenii, and Gaura coccinea, but feeding bouts were also short on these plants. No common sunflowers were present at this site. The research in Arizona disclosed a remarkable degree of omnivory and predation by the plains lubber grasshopper. A large part of the diet of 15 closely observed females consisted of animal matter. Foraging on the ground, the females ate incapacitated insects and even captured and ate smaller melanopline grasshoppers.
Laboratory food preference tests conducted in Texas revealed that the plains lubber grasshopper preferred common sunflower, western ragweed, and cotton seedlings. Two-choice tests conducted in Wyoming showed that dandelion, prairie sunflower, and annual sowthistle were also preferred food plants.
The plains lubber grasshopper disperses and migrates by crawling and hopping. Entomologists have frequently observed adults crossing highways and country roads. Just how fast and how far they travel have not been determined. It is known that from roadsides and field margins they invade fields of young cotton plants. Brief observations of hopping behavior of adult females were made on a dirt road at the Guernsey, Wyoming, airport on the afternoon of 31 July Unflushed hops of females measured 3 to 4 inches.
Flushed hops of two females measured 14 inches each. No data on males were obtained; however, Ernest Tinkham, while studying the ecology of grasshoppers inhabiting the Trans-Pecos region of Texas, observed that male plains lubber grasshoppers could jump 9 feet in a single leap.
The plains lubber grasshopper is a large colorful species Fig. The robust adults are flightless possessing only short, round wings; the tegmina are pink and marked by conspicuous black dots that occasionally coalesce. The body is strikingly striped and banded green, brown, and pink. The disk of the pronotum is trapezoidal and surfaced with a dense number of small knobs and several short wrinkles Fig.
The hindlegs are large and multicolored; the male's hind femora are noticeably larger than the female's Fig. The nymphs are identifiable by their color patterns, shape, and external structures Fig. Head green, tan, or fuscous; antennae filiform and chiefly black, each segment with distal ivory annulus, subocular groove black, instars I and II with vertical ivory bar in front of eye on each side of the frons; compound eyes dark brown.
Pronotum: disk and lateral lobes trapezoidal, median carina distinct, black, and entire uncut , lateral carinae distinct, black and cut once in front of middle, disk banded pink and green with dense number of small knobs Fig. Mesonotum smooth and shiny black see Fig.
Metanotum knobbed and colored like rest of body. Hind femur patterned, hind tibia hues of orange in instars I to IV, orange or yellow in instar V. Phenologically, the plains lubber grasshopper belongs to the intermediate group of grasshopper species.
Hatching has been observed to start in eastern Kansas in mid May, in northern Colorado and in Wyoming during the first week of June, and in Montana in mid June. In southeast Arizona hatching appears to be retarded until the summer monsoon rains first wet the soil. A fifth instar nymph collected 7 August in San Rafael Valley indicated that hatching occurred the first part of July.
Research of the USDA Grasshopper Laboratory has revealed that the eggs of this species require two years of incubation and overwintering before they hatch.
In addition to the laboratory evidence, field observations in Montana, Wyoming, and Texas show higher populations in alternate years, which likewise indicate a two-year life cycle. Oviposition depth depends on female size and soil moisture and density Herrmann et al.
The plug allows the hatching nymphs to easily reach the soil surface. Females preferentially oviposit at sites containing previously laid egg pods, suggesting that egg pods release attractive or arresting pheromones Stauffer et al.
This behavior leads to aggregation of pods Capinera and Scherer Females can produce pods about every 2 weeks, each pod containing 25—50 eggs, and each female can produce 1—3 pods Hunter-Jones , Stauffer and Whitman Grasshopper longevity and reproductive output show geographic and genetic variation Gunawardene et al.
Eggs require a cool period e. Eggs hatch when exposed to warmer temperatures. Typically, egg hatch occurs in the morning Capinera and Scherer Eastern lubbers have a wide host range. Feeding has been observed on at least species from 38 plant families, though their mouthparts are best adapted for feeding on forbs broad-leaf plants , not grasses Squitier and Capinera Watson reported that nymphs preferentially fed on narcissus, Narcissus spp.
Caryophyllales: Phytolaccaceae , as well as several semi-aquatic plants. Watson also noted that nymphs were attracted to fields of narcissus and developed most rapidly when fed narcissus, compared to other host plants. Squitier and Capinera confirmed that lubbers readily feed on a variety of semi-aquatic plant species, including cattail, Typha latifolia L.
Poales: Typhaceae , common arrowhead, Sagittaria latifolia Willd. Alismatales: Alismataceae , poorland flatsedge, Cyperus compressus L. Small Caryophyllales: Polygonaceae. Capinera compared lubber feeding on plant species, standardized to consumption of Romaine lettuce, Lactuca sativa L. Test plants included ornamental, garden, weed, shrub, tree, vine, and aquatic or semi-aquatic species. Generally, lubber grasshoppers preferred young foliage over old foliage.
Plant species that were readily consumed by grasshoppers represented 14 plant families, including amaryllis, Amaryllis spp. Osbeck Sapindales: Rutaceae , demonstrating that eastern lubber grasshoppers are broadly polyphagous.
Diet breadth has a significant effect on lubber defensive chemistry. Jones et al. However, lubbers fed an onion diet sequestered threefold more sulfur-containing plant defensive compounds that were more effective in repelling predators, compared to lubbers fed natural or artificial diets Jones et al. Hatle and Spring also found that lubbers fed a diet of onion produced more secretion and had higher concentrations of total sulfur in their secretions than lubbers fed other diets.
However, the variety of plant toxins sequestered from a broad diet also may augment the efficacy of lubber defenses Chapman and Joern In addition, lubbers readily accept exotic hosts, such as catnip, Nepeta cataria L. Lamiales: Lamiacea , and sequester or synthesize new defenses from the novel chemicals derived from these hosts Blum et al. For example, Snook et al.
This catechol apparently was synthesized from caffeoyltartronic acid derived from catnip leaves. Lubber grasshoppers are protected from most vertebrate and invertebrate predators by the combination of chemical defense and warning coloration Jones et al. The bold coloration of lubbers advertises toxic chemicals to would-be predators, but even young nymphs that produce less chemical defense are avoided by lizards Hatle and Townsend , Hatle et al.
Birds and mammals vomit violently after ingesting a lubber Fig. Yousef and Whitman reported that 21 tested bird and lizard species were unable to consume lubbers and some died. Loggerhead shrikes, Lanius ludovicianus L. Passeriformes: Laniidae , captured lubbers and impaled them on thorns or barbed wire fences. After 1—2 days the toxins degraded, and the shrikes were able to eat the dead lubbers Yousef and Whitman Carolina anole, Anolis carolinensis Voigt Iguania: Dactyloidae , vomiting adult eastern lubber grasshopper.
However, lubbers are vulnerable to a variety of parasites. Lamb et al. Two sarcophagids, Blaesoxipha opifera Coquillett and Blaesoxipha hunteri Hough Diptera: Sarcophagidae , also parasitize lubbers. Larvae develop within the nymphs, killing their hosts upon emergence Capinera and Scherer Lange et al.
This microsporidian infects the gastric caecae and midgut tissues of lubber hosts. In the laboratory, all lubbers became infected, but mortality varied among populations, with lubbers from Georgia and Louisiana becoming lethargic and dying quickly, whereas lubbers from Florida showed no symptoms Lange et al.
Because lubber nymphs are gregarious, they can completely defoliate host plants on which they congregate Capinera Adult lubbers cause less damage than might be expected for their size Capinera and Scherer Defoliation is most often observed in areas that support weeds or semi-aquatic plants, such as irrigation and drainage ditches and edges of ponds. Consumption of at least some weed hosts could be beneficial, if their removal leaves more palatable vegetation for livestock feeding.
However, lubbers may disperse from these sources to crops and residential areas, where they cause more conspicuous, if less extensive, damage. Loss of tissues may not be entirely damaging to host plants, however.
Plants often tolerate or compensate for loss of tissues to grasshoppers or other herbivores, in response to pruning of less productive plant parts Mattson and Addy , Trumble et al. Grasshoppers and other herbivores also can increase primary production at low to moderate levels of herbivory through changes in plant species composition Belovsky and Slade , ; Schowalter Grasshoppers and other herbivores typically deposit salivary fluids on plant tissues as they feed.
These materials may signal plants to recognize herbivore damage and respond in various ways, including compensatory responses and induced defenses targeted to particular herbivore species Schmelz et al. In particular, Dyer et al. Moench Poales: Poaceae , suggesting a mechanism whereby herbivores can increase plant productivity at low to moderate levels of herbivory and thereby stabilize primary production and ecosystem services in natural ecosystems Schowalter Eastern lubbers are not management concerns in forests or other natural areas, although they may periodically cause localized defoliation Drooz Their large size and defensive behavior make them appear to be more serious threats than warranted.
Nevertheless, lubber grasshoppers can cause substantial losses in young citrus orchards, vegetable gardens, and landscaping plants in areas bordering lubber habitats or when lubbers are numerous Kuitert and Connin , Capinera However, damage is rarely significant in older orchards or landscape plantings Capinera Insecticides are rarely warranted, and other options are preferred where lubbers are a nuisance.
As recommended for most grasshoppers and other nuisances, monitoring of lubber abundance and early treatment of areas where nymphal development occurs are the best ways to prevent damage to economically important plants.
Where lubbers are a nuisance, mowing bordering vegetation can be an effective preventative treatment because short vegetation is less favorable to grasshoppers, perhaps by altering thermal balance or exposing them to parasites Capinera and Scherer A number of ornamental plant species, especially amaryllis, spider lily, swamp lily, and oleander, that are particularly susceptible to lubber grasshopper have become widely planted in Southern residential landscapes.
In areas where lubber grasshoppers historically have been a problem, other less preferred ornamental species arerecommended. Maintaining less preferred host plants also may increase the efficacy of insecticide use, when necessary Barbara and Capinera Capinera found that insecticide-laced bait caused significantly higher mortality to lubbers in cages containing non-preferred plant species than in cages with preferred plant species.
When control of lubbers is necessary, especially in residential ornamental plantings, they can be hand-picked and killed by throwing them into a bucket of soapy water or a trash bag Capinera and Scherer If there are too many to control by hand-picking, especially in orchards and crops, insecticides can be applied. However, small amounts of insecticide residue on sprayed plants often are not adequate to kill these insects because of their ability to detoxify plant chemicals and because adult lubbers are too large to be killed easily even with direct contact Capinera and Scherer Insecticides containing carbaryl, bifenthrin, cyhalothrin, permethrin, and esfenvalerate as active ingredients will kill lubbers Capinera and Scherer , especially when applied directly on nymphs.
Spinosad is a microbial product that is relatively safe to use where children or pets are concerned, but it is rather slow-acting, so results may not be apparent for a few days. Given the flightless nature of these insects, insecticide need not be applied broadly. Insecticides should only be used according to label directions, especially near residential areas, water, or food crops. Belovsky and J. Lockwood provided constructive comments on the manuscript. This manuscript is published with approval of the Director of the Louisiana Agricultural Experiment Station, as manuscript number Barbara , K.
Development of a toxic bait for control of eastern lubber grasshopper Orthoptera: Acrididae. Google Scholar. Belovsky , G. Insect herbivory accelerates nutrient cycling and increases plant production. Natl Acad. USA 97 : — Grasshoppers affect grassland ecosystem functioning: spatial and temporal variation. Basic Appl. Blum , M. Ingested allelochemicals in insect wonderland: a menu of remarkable functions.
Severson , R. Arrendale , D. Whitman , P. Escoubas , O. Adeyeye , and C. A generalist herbivore in a specialist mode: metabolic, sequestrative, and defensive consequences. Capinera , J. Host plant selection by Romalea microptera Orthoptera: Romaleidae. Featured creatures: eastern lubber grasshopper. Google Preview. Carolina Biological Supply Co. On the cutting edge: grasshopper dissection. Chapman , R.
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