Placed on the Web 3/95 by the Department of Entomology, NCSU
Wildlife is a valuable natural resource. Most orchardists enjoy seeing wildlife on their farm, and many benefit economically by leasing hunting and fishing rights to sportsmen. In North Carolina, more than $1.1 billion is spent annually by hunters and fishermen alone.
Orchards attract wildlife by providing food, cover, and nesting areas. Birds such as bobwhite quail nest in grassy understories, while songbirds and mourning doves nest in fruit trees.
Pesticides used in orchard management may harm wildlife directly or indirectly. Wildlife can be affected directly (can become sick or die) when they are exposed to highly toxic agrichemicals. Wildlife are exposed to pesticides when they eat the residues on plants and in insects. Eggs and young birds in nests may be exposed during spraying operations. Wildlife made sick by pesticides may neglect their young, abandon their nests, and become more susceptible to predation and disease.
Pesticides indirectly affect wildlife when the quantity or quality of their habitats is reduced. For instance, insecticides that drift into a stream can kill aquatic invertebrates and reduce food supplies for ducks or fish. When herbicides are sprayed on wildlife habitats, valuable vegetative cover is reduced.
Careful selection and use of pesticides, however, can lessen their impact upon wildlife. This publication (1) describes how pesticides used in fruit production can harm wildlife and (2) describes how farmers can minimize adverse effects of pesticides on wildlife.
Tables 1, 2, and 3 list insecticides recommended i the North Carolina Agricultural Chemicals Manual for use on fruit crops. Table 1 rates insecticides according to their toxicities to birds, mammals, and fish. The effects of insecticides on wildlife and fish can be minimized by using the least toxic alternatives. Insecticides in Tables 2 and 3 are rated low, moderate, or high based on the hazard their use presents to wildlife (birds and mammals). The hazard of an insecticide is based on its toxicity to wildlife, the way it is used, and other characteristics, such as its persistence in the environment. For example, methomyl (Lannate) is acutely toxic to birds and mammals (Table 1). However, because methomyl does not persist in the field, careful use of this chemical presents only a moderate hazard to wildlife (Table 2). Wildlife exposed to insecticides rates high may die or become sick. Insecticides rated moderate may also cause death or sickness, although death is unlikely. Insecticides rated low are unlikely to harm wildlife directly.
Table 1. Toxicities of Insecticides and Miticides Used on Fruit Crops to Birds, Mammals, and Fish.
Pesticide (Brand Name) Birds* Mammals* Fish**
azinphos-methyl (Guthion) H H EH carbaryl (Sevin) L L H chlorpyrifos (Lorsban) H L EH diazinon (Diazinon) H*** M EH dicofol (Kelthane) L L EH dimethoate (Defend) H*** M M dinocap (Karathane) M L EH endosulfan (Thiodan) M H EH esfenvalerate (Asana) L L EH formetanate (Carzol) M H M fenbutatin-oxide (Vendex) L L EH malathion L L EH methidathion (Supracide) H M EH methomyl (Lannate) H H H methyl parathion (Penncap-M) H*** H H oxamyl (Vydate) H H M oxythioquinox (Morestan) - L EH permethrin (Ambush, Pounce) L L EH phosmet (Imidan) L M EH propargite (Omite) L L EH
*Wildlife hazard is based on the following toxicities: H (Highly toxic) = LD50 less than 30 mg/kg and LC50 less than 500 ppm.
M (Moderately toxic) = LD50 greater than 30 and less than 100 mg/kg and/or LC50 greater than 500 and less than 1,000 ppm. L (Low toxicity) = LD50 greater than 100 mg/kg and LC50 greatre than 1,000 ppm. NT (Not toxic) **Fish 96-hour LC50 toxicities are as follows: EH (Extremely toxic) less than 0.1 ppm H (Highly toxic) 0.1 to 1.0 ppm M (Moderately toxic) 1 to 10 ppm L (Low toxicity) greater than 10 ppm To convert fish toxicities to pounds of active ingredient per acre-foot of water, multiply by 2.7. ***Active ingredient (not necessarily a specific product) has caused wildlife deaths. Table 2. Hazard of Insecticides Used on Apples to Wildlife.
Insecticide Wildlife Insect (Brand name) hazard* Kills** Comments
During Green Tip to 1/2-inch Green
Scales, European superior oil Chlorpyrifos and methi- red mites, and (Supracide) low no dathion are extremely toxic rosy apple aphid methidathion moderate no to fish. eggs chlorpyrifos (Lorsban) moderate no
Tight Cluster to Pink
European red mite oxythioquinox low no (early season) (Morestan)
Rosy apple aphid esfenvalerate Esfenvalerate, permethrin, (Asana XL) low no and endosulfan are very permethrin toxic to fish. Phosphamidon (Pounce, may be cancelled in 1992. Ambush) low no endosulfan (Thiodan) moderate no oxamyl (Vydate) moderate no dimethoate (Cygon) high yes phosphamidon (Dimecron) high yes
Spotted tentiform esfenvalerate Methomyl and oxamyl are leafminer control (Asana XL) low no more toxic to wildlife (preventive) permethrin than formetanate. (Pounce, Ambush) low no formetanate (Carzol) moderate no methomyl (Lannate) moderate no oxamyl (Vydate) moderate no endosulfan (Thiodan) moderate no
Tarnished plant esfenvalerate bug (Asana XL) low no Esfenvalerate, permithrin, permethrin and endosulfan are very (Pounce, toxic to fish. Ambush) low no formetanate (Carzol) moderate no endosulfan (Thiodan) moderate no dimethoate (Cygon) high yes
Petal Fall to First Cover
Codling moth phosmet (Imidan) low no Azinphos-methyl is rated azinphos-methyl high because of its (Guthion) high no toxicity. Nonformulated formulated methyl parathion has caused methyl parathion wildlife deaths. (Penncap-M) moderate yes
Green fruitworms chlorpyrifos Chlorpyrifos may be safer (Lorsban) moderate no than methomyl when wildlife methomyl are exposed directly. (Lannate) moderate no endosulfan (Thiodan) moderate no dimethoate (Cygon) high yes
Plum curculio phosmet See codling moth comments. (Imidan) low no Chlorpyrifos is less toxic azinphos-methyl to birds and mammals than (Guthion) high no methyl parathion. chlorpyrifos (Lorsban) moderate no formulated methyl parathion (Penncap-M) moderate yes
Rosy apple aphid endosulfan Phosphamidon may be (Thiodan) moderate no cancelled in 1992. dimethoate (Cygon) moderate yes phosphamidon (Dimecron) high yes
Spotted tentiform methomyl leafminer (Lannate) moderate no
White apple carbaryl Formetanate is less toxic leafhopper (Sevin) low no to wildlife than methomyl. formetanate (Carzol) moderate no methomyl (Lannate) moderate no dimethoate (Cygon) high yes
Second and Later Cover Sprays
Apple maggot phosmet Nonformulated methyl para- (Imidan) low no thion has caused wildlife azinphos-methyl deaths. Azinphos-methyl is (Guthion) high no rated high because of its chlorpyrifos toxicity to wildlife. (Lorsban) moderate no dimethoate (Cygon) high yes formulated methyl parathion (Penncap-M) moderate yes
Codling moth phosmet Azinphos-methyl is rated (Imidan) low no high because of its azinphos-methyl toxicity. Nonformulated (Guthion) high no methyl parathion has formulated caused wildlife deaths. methyl parathion (Penncap-M) moderate yes
European redmite, sulfur Dicofol, propargite, and (many brands) low no dinocap are a hazard to twospotted spider summer oils fish. (many brands) low no propargite (Omite, Comite) low no dinocap (Karathane) low no formetanate (Carzol) moderate no dicofol (Kelthane) low no
Green and spirea chlorpyrifos Phosphamidon is likely to apple aphid (Lorsban) moderate no be cancelled in 1992. dimethoate (Cygon) high yes phosphamidon (Dimecron) high yes
Spotted tentiform methomyl leafminer (Lannate) moderate no oxamyl (Vydate) moderate no
Tufted apple chlorpyrifos See codling moth comments. budmoth (Lorsban) moderate no Chlorpyrifos is less toxic formulated to wildlife than methyl methyl parathion parathion. (Penncap-M) moderate yes
White apple carbaryl Formetanate is less toxic (Sevin) low no to wildlife than methomyl. leafhopper formetanate (Carzol) moderate no methomyl (Lannate) moderate no endosulfan (Thiodan) moderate no dimethoate (Cygon) high yes
*Wildlife hazards: high indicates possible wildlife sickness, deaths less likely; moderate indicates possible wildlife sickness, deaths less likely; low indicates sickness unlikely. **Kills: yes indicates wildlife deaths due to use of the insecticide (active ingredient) have been reported. no indicates wildlife deaths have not been reported when pesticide is used according to label. Table 3. Hazard of Insecticides Used on Nectarines and Peaches to Wildlife.
Insecticide Wildlife Insect (Brand Name) hazard * Kills** Comments
Scales, spider superior oil No information is mites (many brands) low no available on wildlife effects.
Petal Fall and Shuck Split to Shuck Fall
Tarnished plant esfenvalerate Azinphos-methyl is highly bugs, stink bugs, (Asana XL) low no toxic to wildlife. All are plum curculio, permethrin extremely toxic to fish. oriental fruit (Pounce, moth Ambush) low no azinphos-methyl (Guthion) high no endosulfan (Thiodan) moderate no
White peach esfenvalerate Nonformulated methyl para- scale, plum (Asana XL) low no thion has caused wildlife curculio, spider permethrin deaths. (Pounce, Ambush) low no azinphos-methyl (Guthion) high no formentanate (Carzol) moderate no formulated methyl parathion (Penncap-M) moderate yes
Peachtree borers esfenvalerate All are highly toxic to (Asana XL) low no fish. endosulfan (Thiodan) moderate no chlorpyrifos (Lorsban) moderate no
Spider mites fenbutatin-oxide Fenbutatin-oxide, propar- (Vendex) low no gite, and dicofol are very propargite toxic to fish. (Omite, Comite) low no formetanate (Carzol) moderate no dicofol (Kelthane) low no
*Wildlife hazards: high indicates possible wildlife deaths; moderate indicates possible wildlife sickness, deaths less likely; low indicates sickness unlikely. **Kills: yes indicates wildlife deaths due to use of the insecticide (active ingredient) have been reported. no indicates wildlife deaths have not been reported when pesticide is used according to label.
Applying insecticides more than once every 10 to 14 days increases the risk to wildlife, even when moderately toxic pesticides are used. Wildlife that have not fully recovered from a previous exposure to an insecticide are more likely to die if they are exposed again. Therefore, when multiple sprays are needed, it is very important to use the least toxic pesticide available.
To reduce danger to wildlife from liquid insecticides:
Pesticides applied with low-pressure sprayers are less likely to drift off target than those applied using high-pressure, air-blast sprayers or ultra-low-volume (ULV) sprayers. Ultra-low-volume formulations are more hazardous to fish and wildlife than conventional sprays because they often approach 100 percent active ingredient and have a high potential to drift.
Although fumigants are highly toxic, their activity is of short duration and they have not been reported to cause wildlife poisonings. Nemacur (fenamiphos) may present a greater hazard to wildlife since it is highly toxic and remains active longer. Nemacur has been reported to cause wildlife deaths. When possible, use Telone (dichloropropene) to minimize the hazard to wildlife.
Benlate, thiophanate-methyl (Topsin-M), and copper sulfate are extremely toxic to earthworms and other soil invertebrates. In some orchards, most soil animal life (including large earthworms) has been eliminated by the extensive use of copper-containing fungicides. Therefore, these fungicides can reduce food supplies for some mammals and birds.
Overall, however, herbicides used in orchards do not present a direct hazard to wildlife. Herbicides can adversely affect wildlife when their use destroys the habitat surrounding orchards. Care should be taken to avoid spraying herbicides into wildlife habitat.
Farmers can reduce exposure of nontarget wildlife to pelleted baits by placing the baits in active runways. The best location for rodent baits is where two or more runways intersect. Hand placing baits requires half the amount of rodent bait per acre of orchard and has the same efficacy as broadcast distribution but costs more over large areas.
Additional publications in the Pesticides and Wildlife series include:
Pest and Orchard Management Guide for North Carolina Apples, AG-37
Peach and Nectarine Disease and Pest Management Guide, AG- 146S