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Experiments were conducted in Western Washington on the control of slugs affecting orchard grass-ladino white clover pastures. Slug populations for the most part consisted of Deroceras agreste (Linnaeus) and Arion ater (Linnaeus) although several other species were found. The best method of determining slug populations in pastures involved the use of boxes. It was found that slugs would seek shelter under upturned boxes during the day if the boxes were made light-proof. It was demonstrated that slugs could destroy ladino white clover in a single growing season. Slug populations varied greatly within a season. The slug Population was greatly increase at the surface by over head irrigation. When colloidal suspensions of metaldehyde were pumped into the irrigation system at this time, seasonal control of slugs was obtained.

Ethylene dibromide and 1,2-dibromo-3-chloropropanc were ineffective in controlling the garden symphylid, Scutigerella immaculata (Newport), when applied to established crops. When tested under controlled conditions, methyl bromide was found to be the most effective fumigant. Of the fumigants that could be applied with a chisel-type applicator, 1,3-dichloropropene was the most. effective ingredient. Chloropicrin, Vapam® (sodium methyldithiocarbamate) ethylene dibromide, 1,2-dibromo-3- chloropropane, and 1,2-dichloropropane were ineffective against symphylids when tested under controlled conditions. In controlled experiments conducted under field conditions, 10 gallons of 1,3-dichloropropene gave satisfactory control in light soils.

The carrot rust fly ( Psila rosae (F.)) is normally controlled in Washington by soil and surface applications of chlorinated hydrocarbons. In 1957 a strain of Psila rosae highly resistant to the chlorinated hydrocarbons appeared in the Lake Sammamish region in northwestern Washington. The carrot crop was destroyed despite repeated soil and surface treatments with chlorinated hydrocarbons. Twenty-two compounds, including chlorinated hydrocarbons and organic phosphates, were tested as soil or furrow treatments. Am. Cyanamid 18133 ( 0,0 -diethyl 0 -2- pyrazinyl phosphorothioate), dicapthon, and parathion gave fair control when used as furrow treatments. Diazinon® ( 0,0 - diethyl 0 -(2-isopropyl-4-methyl-6-pyrimidinyl) phosphorothioate gave outstanding control as a furrow treatment when used at rates of 1, 2, 3 or 4 1bs. of active ingredient per acre. Diazinon was ineffective at 5 pounds per acre when used as a total soil treatment. All other compounds tested were ineffective when used as soil or furrow treatments.

Strains of onion maggot ( Hylemya antiqua (Meig.)) highly resistant to the chlorinated hydrocarbon insecticides appeared in certain areas of the Pacific Northwest. Furrow treatments, seed treatments, and multiple surface applications of chlorinated hydrocarbons were ineffective. Seed, soil and surface treatments with organic phosphates did not give economic control. Furrow treatments of Guthion, Diazinon, ethion, Trithion, V-C 13, and Bayer 21/199 gave excellent control. Furrow treatments with malathion, Dipterex, Perthane, Bayer 19639, Sevin, Thiodan, DDT, Kepone, Dow ET-57, and endrin were ineffective. Thimet gave good control as a furrow treatment, but was phytotoxic. Parathion applied in the furrow protected onions for several weeks, then declined rapidly.

Basil' toxicities of compounds against Scutigerella immaculata Newport were determined by bioassay methods. To simulate field conditions, bioassay tests were conducted by mixing insecticides with required amounts of soil to give mixtures that contained 2.5 p.p.m. of the insecticides. With the exception of lindane, the chlorinated hydrocarbons had little effect on this pest. Of the 46 compounds tested, only parathion, UCC 8305 (P-chloro-2, 4-dioxa-5-methyl- P-thiono-3-phosphabicyclo (4.4.0) decane), V-C 13 ( O -2,4-dichlorophenyl O,O -diethyl phosphorothioate), Am. Cyanamid E.N. 18133 ( O,O -diethyl O -2-pyrazinyl phosphorothioate) and lindane were initially toxic and possessed some degree of residual effectiveness. Am. Cyanamid E.N. 18133 gave outstanding results and appeared to be the most promising of the insecticides tested.

Strains of cabbage maggot ( Hylemya brassicae (Bouche)) highly resistant to chlorinated hydrocarbon and organic phosphate insecticides appeared in certain areas of the Pacific Northwest. Thirty-three compounds were tested as granules or drenches applied at planting time with cruciferous crops. All were ineffective except Zinophos ( O,O -diethyl O -2-pyrazinyl phosphorothioate) which gave outstanding control. LD-50 tests demonstrated that the adults were highly resistant to chlorinated hydrocarbons but still susceptible to organic phosphates. A drench of Zinophos or Guthion® ( O,O -dimethyl S .(4-oxo-1,2,3- benzotrazin-3-(4 H )-ylmethyl) phosphorodithoate) applied to transplants of cauliflower or cabbage provided excellent control against cabbage maggot attacks.

From 1955 to 1957 a total of 54 acres were established in field plots to evaluate compounds for the control of Scutigerella immaculata Newport. Productive results were obtained in approximately 10% of the plots. Interpretation of results was complicated in the remainder of the plots by the irregular distribution pattern, non-feeding phases, and preferential feeding habits of the pest. Although it failed to give control in some trials, parathion used as a soil treatment at the rate of 5 pounds of active ingredient per acre consistently gave better results than any other insecticides tested.

Experiments were conducted in western Washington on the control of slugs affecting vegetables and strawberries using metal-dehyde baits, sprays, and dusts. Slug populations for the most part consisted of Deroceras reticulatum (Muller) and Arion ater (Linnaeus); although other species including Prophysaon andersoni (Cooper), Milax gagates (Linnaeus), Arion circumscriptus (Johnston), and Limax maximus Linnaeus were present. The best method of determining slug populations was to establish bait stations in plots. Baits were placed under boards; then dead slugs were collected from the bait stations. Metaldehyde dusts and sprays reduced slug populations in bean and corn plantings. In strawberry plantings, metaldehyde sprays and dusts were superior to baits in reducing populations. Metaldehyde sprays and dusts were effective only when the boom was lowered to within a few inches of the ground. No control was obtained when the materials were applied above the foliage.

Several insecticides were tested for ovicidal activity on spotted tentiform leafminer (STLM), Phyllonorycter blancardella (F.). In one laboratory experiment, fenvalerate and methomyl caused 88 and 72% egg mortality, respectively, whereas endosulfan was less effective (29.6% egg mortality). The control (water) had the lowest egg mortality (8%). In a second laboratory experiment, fenvalerate, permethrin, and methomyl caused 92, 92, and 77% egg mortality, respectively, whereas the control showed low egg mortality (13%). In field applications, fenvalerate and diflubenzuron were effective ovicides (100 and 70.7% egg mortality, respectively). Single-tree applications of fenvalerate and diflubenzuron showed both treatments to be ovicidal at low rates. Insecticides targeted at the egg stage and applied before hatch add a new dimension to STLM management.

Treatments were applied to a completely randomized block. Each treatment consisted of single trees replicated 4 times. Dilute sprays were applied in 285 gal and concentrate sprays were applied in 67 gal of finished spray per acre by a Bean orchard sprayer. Sprays were applied on 2 schedules full season (26 Apr, 11 May, 25 May, 6 Jun, 17 Jun, 28 Jun, 10 Jul, 22 Jul, 2 Aug, 14 Aug, 26 Aug) and partial season (25 May, 6 Jun, 17 Jun, 28 Jun, 10 Jul, 22 Jul, 2 Aug, 14 Aug, 26 Aug). Evaluations were made by examining 100 apples per replication for injury and categorizing injuries by their respective pest. Mite counts were made by controlling 50 leaves from each replication and brushing them in a mite brushing machine. Resulting plates were examined using a stereo binocular microscope recording numbers of ERM, TwoSpotted Spider Mites, and predaceous mites on each plate.

Field trials were conducted to evaluate the effectiveness of various insecticides against climbing cutworms in vineyards in southwestern Michigan. Amathes c-nigrum (L.), Agrotis badinodis (Grote), and Euxoa messoria (Harris) were the predominate species. In established vineyards, damage to developing buds was evaluated; in nonproducing vineyards, mortality and survival of cutworms were measured. In trials during 1978 and 1979, fenvalerate, and permethrin provided significantly less bud damage. All materials tested provided some control of the cutworms, but the 1979 test found that permethrin, fenvalerate, chlorpyrifos, and the high rate of fenamiphos were best.

A leafminer of apple, Lithocolletis blancardella F., has 3 generations/year in southwestern Michigan apple orchards. Apanteles ornigis Weed, Sympiesis conica (Provancher), S. marylandensis Girault, and Pnigalio flavipes (Ashmead) are natural enemies of leafminer larvae. Total leaf area can be reduced 32% by leafmining larvae. Many broad spectrum and systemic insecticides effectively control this leafminer and certain carbamate and organophosphate insecticides cause a significant reduction in parasitism of the larvae.

The garden symphylan, Scutigerella immaculata (Newport) was effectively controlled in mint by 5 lb/acre of Zinophos (O,O -diethyl O -2-pyrazinyl phosphorothioate) or 10 lb of Nemacide® (O (2,4-dichlorophenyl) O,O -diethyl phosphorothioate) applied to the soil just prior to plowing the mint in late fall. Spring applications of these 2 chemicals or 5 lb/acre of parathion just before tillage were also effective. Only 2 lb of Zinophos were needed for good control in the spring.

Treatments were applied to a completely randomized block. Each treatment consisted of single trees replicated 4 times. Sprays were applied in 74 gal of finished spray per acre by a Bean orchard sprayer. Evaluations were made by examining 100 apples per replication for injury and categorizing injuries by their respective pest. Sprays were applied as follows: Materials on ca. 2-wk interval were applied 25 Apr at pink (P), 9 May at petal fall (PF), 21 May, 1 Jun, 12 Jun, 25 Jun, 8 Jul, 22 Jul, 8 Aug, 26 Aug, 9 Sep, 23 Sep. The ca. 7-day Methomyl was sprayed 25 Apr at pink (P), 10 May at petal fall (PF), 20 May, 29 May, 5 Jun, 12 Jun, 18 Jun, 25 Jun, 2 Jul, 12 Jul, 21 Jul, 29 Jul, 8 Aug, 19 Aug, 26 Aug, 5 Sep, 12 Sep, 17 Sep.

A randomized complete block design was used. Each block was composed of 10 rows with 12 bushes in each row. Each treatment was randomly assigned to 1 row in each of 4 blocks. One buffer row was left between treatments in each block. Materials were applied by a hand-held CO2 sprayer dilute to drip on 6 Jun and 19 Jun. Evaluation consisted of examining 5 berry clusters from each of 10 bushes (50 clusters per treatment per block) in each treated row. The damage was categorized as cherry fruitworm if the entry point was near the calyx end and cranberry fruitworm if the entry point was near the stem end.

Treatments consisted of single trees replicated 4 times in a completely randomized design. Materials were applied dilute by handgun on 7 May (petal fall), 4 Jun and 2 Jul. On each sample date 50 leaves were randomly sampled from each of the 4 trees. A subsample of 25 leaves were examined for psylla nymphs using a stereo microscope. All 50 leaves were then brushed in a mite brushing machine and the number of rust mites recorded for 8 sections.

A randomized complete block design was used. Treatments consisted of single trees in each of 4 blocks. Trees were selected which had existent mite populations. These trees were sampled and the numbers of mite per leaf determined. The trees were then divided into 4 blocks based on similarity of the counts. Each treatment was then randomly assigned to a tree in each block (blocked by precount). Evaluations were by the following: From each tree 50 leaves were selected at random. The leaves were brushed in a mite brushing machine and the resulting plates examined for ERM. The numbers were recorded as counts per 8 sections of the plate and converted to mites per leaf. OMITE was applied at 138 gpa on 2 Aug. ABG-6162 was applied dilute (DIL) by handgun or concentrate (CONC) 36 gal/acre as noted on 3 Aug and 13 Aug.

Treatments consisted of single rows replicated 4 times. Each row consisted of 8 trees. Materials were applied by handgun dilute on 16 May. Evaluations involved examining each tree for borers using a hammer was based on selecting the most infested trees in the row. Timing of the spray was based on pheromone trap catches using a specific pheromone for APB. A 50% mixture of a polyvinyl aqueous butyral dispersion (PVB) was used with insecticides. In addition, Vapor Gard (an anti-desiccant that also acts as a UV screen and sticker) was tested.

Treatments consisted of 0.14 acre blocks replicated 4 times. On 26 Jul 3785 ml/acre of MIT AC 1.5 EC was applied to a psylla population which had developed pyrethroid tolerance to reduce the population prior to randomization of this experiment. Materials were applied by airblast sprayer on 2 Aug, 16 Aug and 29 Aug in 78 gal/acre. At each sample period 25 leaves were randomly selected from the center 4 trees of each block, resulting in 100 leaves per replication (400 per treatment). This sample of 25 leaves from each tree was examined for psylla nymphs using a stereo microscope.

Treatments consisted of unreplicated 0.19-acre blocks. Materials were applied by airblast sprayer in 116 gpa. Alsystin and F4999 were applied on 22 Apr (green tip), 26 Apr (tight cluster), 2 May (white bud), 9 May (petal fall = PF), 24 May, 7 Jun, 24 Jun, 8 Jul, 22 Jul, 7 Aug and 21 Aug. Mitac was applied on 9 May (PF), 8 Jul, 7 Aug and 21 Aug. All other materials were applied on 9 May, 24 May, 7 Jun, 24 Jun, 8 Jul, 22 Jul, 7 Aug and 21 Aug. On each sample date 50 leaves were randomly sampled from each of 4 centrally located trees in each block. A subsample of 25 leaves were examined for psylla nymphs using a stereo microscope. All 50 leaves were then brushed in a mite brushing machine and numbers of RM recorded for 8 sections. For broad spectrum pests 50 fruit were sampled from the 4 sample trees and examined for insect damage. Damages were categorized by their respective pest.

Treatments consisted of unreplicated 0.5 acre blocks. Treatments were applied by airblast sprayer. Sprays were applied on 19 Jun, 1 Jul, 11 Jul, 23 Jul, 6 Aug, 20 Aug and 4 Sep to all treatment except Dimilin + Nu-Lure. Dimilin + Nu-Lure received sprays on 19 Jun, 11 Jul, 1 Aug and 20 Aug. The treatments were evaluated by randomly picking 100 fruit from each of 4 trees in the center of each block, resulting in 400 apples per treatment being evaluated. The apples were then examined for AM damage and the results recorded. Nu-Lure is a liquid feeding attractant for AM.

A completely randomized block design was used. Treatments consisted of vines per replicate, replicated 4 times. Materials were applied by airblast sprayer in 99 gal/acre on 5 Jun, 17 Jun, 28 Jun, 11 Jul, 23 Jul, 7 Aug, 1 Aug and 5 Sep. Evaluations involved examining 25 bunches of grapes on 13 Sep ’85 for GBM per replicate.

Unreplicated blocks were used. Materials were applied by a hand held CO2 sprayer at 51 gal/a on 17 May, 28 May, 6 Jun and 19 Jun. Evaluation consisted of examining 100 crowns per block and counting the number of leaves infested 24 Jun with leafroller larvae. The mean number of leaves is estimated at 5.

Treatments were applied to a completely randomized block. Each treatment consisted of single trees replicated 4 times. Sprays were applied in 123 gal of finished spray per acre by a Bean orchard sprayer. Sprays were applied on 27 Apr at pink (P), 13 May at petal fall (PF), 28 May, 10 Jun, 24 Jun, 3 Jul, 16 Jul, 29 Jul, 12 Aug, 23 Aug, 5 Sep and 19 Sep. Evaluations were made by examining 100 apples per replication for injury and categorizing injuries by their respective pest. RAA evaluations were made using a 3-min sample search. A single mite count was made in midseason by collecting 50 leaves from each replication and brushing them in a mite brushing machine. Resulting plates were examined using a stereo binocular microscope recording numbers of ERM and predaceous mites on each plate.

Treatments consisted of single trees replicated 4 times. Materials were applied by airblast sprayer in 116 gal/acre on 23 Apr, 3 May, 18 May, 29 May, 11 Jun, 24 Jun, 9 Jul, 23 Jul and 6 Aug. Evaluations involved examining 50 fruit from each replicate for plum curculio damage.

Treatments consisted of unreplicated blocks. Materials were applied by airblast sprayer in 103 gal/acre on 13 Jun, 27 Jun, 9 Jul, 21 Jul, 6 Aug, 20 Aug, 4 Sep and 18 Sep. One nozzle was offset and extended so as to apply ca 20% of the spray volume to the trunks and scaffold limbs. Evaluations involved examining 8 trees in each block for borers.

Treatments were applied to a completely randomized block. Each treatment consisted of single trees replicated 4 times. Sprays were applied in 55 gal of finished spray per acre by a Bean orchard sprayer. Evaluations were made by examining 100 apples per replication for injury and categorizing injuries by their respective pest. A single mite count was made by collecting 50 leaves from each replication and brushing them in a mite brushing machine. Resulting plates were examined using a stereo binocular microscope recording numbers of ERM and predaceous mites on each plate. Material shortages prevented full season applications. Sprays were applied as follows: UC 76963 on 27 Apr at pink (P), 13 May at petal fall (PF), 25 May, 4 Jun, 16 Jul; CME 13411 on 13 Jun, 25 Jun, 16 Jul.

Treatments consisted of unreplicated 0.25 acre blocks. Materials were applied dilute by handgun on 7 May, 12 Jun, 17 Jul and 21 Aug 1985. At each sample period 50 leaves were randomly sampled from each of 4 centrally located trees in each block. A subsample of 25 leaves were examined for psylla nymphs using a stereo microscope. All 50 leaves were then brushed in a mite brushing machine and numbers of RM recorded for 8 sections. For sooty fungus a rating system was developed which included a numeric indicator of the amount of fungus present. 50 leaves were randomly selected from the same trees used above and rated as 1 (no sooty fungus), 2 (sooty fungus just visible), 3 (moderate fungus showing but less than 50% of leaf affected), 4 (severe fungus on greater than 50% of leaf). The mean sum per tree for the four trees sampled in each block is shown below.

Treatments consisted of single, 0.5-acre unreplicated blocks. Materials were applied by handgun to drip on 16 May, 14 Jun, 25 Jun, 8 Jul and 19 Jul. Evaluations involved blending 8 pts of cherries in a blender and sieving the resulting slurry to remove the pulp. The remaining material was then examined for larvae.