1. Garden Pests

2. “A Sure Thing”! Home Gardeners can tolerate a small amount of pest damageHome Gardeners can tolerate a small amount of pest damage Less prone to infestationsLess prone to infestations Your income does not depend on maximum yieldsYour income does not depend on maximum yields

3. Pest problems WeedsWeeds InsectsInsects DiseasesDiseases BirdsBirds AnimalsAnimals Other miscellaneousOther miscellaneous

4. Pesticide “killer of pests”“killer of pests” Typically chemicalTypically chemical –Benefits: rapid and complete control –Problems: dangerous and can pollute the environment Pesticide Applicators Training ManualPesticide Applicators Training Manual Classes offered at UVMClasses offered at UVM Contact Ann Hazelrigg 656-0493Contact Ann Hazelrigg 656-0493

5. Weeds ! A plant out of place!A plant out of place! Growing where it is not wantedGrowing where it is not wanted Competes for:Competes for: –Space (esp. light) –Water –Nutrients May harbor insects and diseaseMay harbor insects and disease

6. Allelopathy “allelon” which means “of each other”, and “pathos” which means “to suffer” chemical inhibition of one plant by anotherchemical inhibition of one plant by another Noted for chickpea by Theophrastus (300 BC) and Pliny the Elder (1 AD)Noted for chickpea by Theophrastus (300 BC) and Pliny the Elder (1 AD)

7. Juglans nigra produces juglandic acid Black Walnut Juglans nigra produces juglandic acid

8. Not all allelopathy is bad! Rye and wheat when used as a cover crop suppressed the development of weeds Sorghum also has potent weed suppression chemicals.

9. Weeds ! Weeds spread by seeds or rhizomesWeeds spread by seeds or rhizomes Weed seeds are long-livedWeed seeds are long-lived Most herbicides are generally NOT recommended for use in a gardenMost herbicides are generally NOT recommended for use in a garden

10. Cultural control of weeds Plastic mulches - porous black plastic or clear plastic (to “cook” weeds) prior to plantingPlastic mulches - porous black plastic or clear plastic (to “cook” weeds) prior to planting Bark mulch - to suppress weeds needs to be 3” deep at least however, avoid “cones” of mulch around the trunk of the tree!Bark mulch - to suppress weeds needs to be 3” deep at least however, avoid “cones” of mulch around the trunk of the tree!

19. Mulch “cone”

27. Rose plant frozen during winter

30. Cultural control of weeds Pull by handPull by hand Hand tools (hoes)Hand tools (hoes)

31. Burning weeds

32. Power equipment

33. Chemical control of weeds Herbicides = “killer of plants”Herbicides = “killer of plants” First developed in the 1930’sFirst developed in the 1930’s –Selective herbicides = kills only certain kinds of plants Ex: 2,4-D kills only broad-leaved plantsEx: 2,4-D kills only broad-leaved plants –Nonselective herbicides = kills all plants it contacts Ex: Roundup ®= GlyphosateEx: Roundup ®= Glyphosate

34. Chemical control of weeds Contact herbicide - injury to parts of the plant the herbicide contactsContact herbicide - injury to parts of the plant the herbicide contacts Translocated herbicide - chemical moves systemically through the vascular system of the plant (Ex: Roundup ®)Translocated herbicide - chemical moves systemically through the vascular system of the plant (Ex: Roundup ®) Residual herbicide - kills during and after applicationResidual herbicide - kills during and after application Nonresidual herbicide - kills only when the herbicide is appliedNonresidual herbicide - kills only when the herbicide is applied

35. Chemical control of weeds Preplant herbicide - applied before the crop is seededPreplant herbicide - applied before the crop is seeded Preemergent herbicide - applied after the crop is seeded but before it comes through the soil surfacePreemergent herbicide - applied after the crop is seeded but before it comes through the soil surface Postemergent herbicide - applied after the crop has emergedPostemergent herbicide - applied after the crop has emerged

36. Chemical control of weeds Herbicides affected by:Herbicides affected by: –Soil texture (sand, silt, clay, OM) –Soil moisture –Light exposure –All the above are important as to how they affect the soil microbes which often are responsible for degrading the chemical –Herbicides persist longer on sandy, dry soils

37. 2,4-D damage to broadleaf weeds Can kill shallow-rooted trees! Never apply if there is a breeze!

38. Garden plant injury from herbicides Sensitive plants:Sensitive plants: –Tomatoes –Grapes –Lilacs –Maples Symptoms:Symptoms: –Curling of leaves –Light color of viens and leaves –Browning and death!

39. Herbicide injury

40. To avoid herbicide injury Spray when the air is stillSpray when the air is still Spray when it is cool (heat volatilizes chemicals)Spray when it is cool (heat volatilizes chemicals) Never use an herbicide sprayer for other spraying purposesNever use an herbicide sprayer for other spraying purposes

41. Biological weed control One living organism used to control anotherOne living organism used to control another Little success with these methods so far for general homeowner use.Little success with these methods so far for general homeowner use.

42. Organic weed control A by-product from corn syrup production seems promising. Sold by Gardens Alive ® as “WOW! ® Plus”.A by-product from corn syrup production seems promising. Sold by Gardens Alive ® as “WOW! ® Plus”. –a pre-emergent –a selective herbicide (only kills broadleaves weeds) –can walk on it after applied –can be used in the vegetable and flower garden on established plants