Our goal as humans, is to OPTIMIZE the growth of our plants.
This requires just the right amount of each of several factors:
AKA: Plant Spacing
Competition increased Yield decreased Higher humidity Yield increased Fungal Growth Yield decreased
Increased heat Yield decreased Increased airflow Yield increased Less fungi Yield increased More water needed Yield decreased Wasted space Yield decreased Weeds invade Yield decreased Erosion increased Yield decreased
1. Thin Seedlings - story about Mrs. Fulton's Tomato Seedlings
2. Plan for mature size of trees and shrubsFoundation Plantings -- windows
Sidewalk and Driveway proximity
Tomato seedlings = weeds
Goldenrod = garden flower in Europe
Weed is in the mind of the gardener!
1. Rapid Growth
2. Mature Young
3. Many Seeds
4. Vegetative spread
5. Stress TolerantBiological Stress (few pests, competitive)6. Longevity in Soil "Seed Bank" (100+ years)
Environmental Stress (deep roots, efficient biochem.)
1. Mechanical Eliminationa. Pulling out by hand (ouch my aching back)2. Mulching
b. Hoeing (too much energy needed)
c. Wheel Hoe (better but many trips down each row)
d. Garden Rake (so that's what it is for!)a. Deep Enough3. Chemical Controls
b. Apply when plants are tall enough, pile it deep (6")
c. Remove when needed
(for thermal insulation: apply anytime AFTER ground is frozen, remove EARLY spring)
d. Water Use Benefits! Soil Conditioning Benefits!
e. Types1. Inorganic = rocks, plastic, etc. - personal favorite: old carpet strips
2. Organic = newspapers, dead leaves, grass clippings, straw, salt marsh hay (NOT HAY)a. Vegetation Killers = Non-selective Herbicide1. arsenic = heavy metal toxinb. Selective Herbicides
2. glyphosate = Roundup = Kleenup = fairly "safe" = plants only
3. boiling water
4. torch1. 2,4-Dichlorophenoxyacetic acid kills broadleaf in grass (suspected carcinogen)
2. Eptam kills grass seedlings in broadleaf crops
3. Trifluralin = Treflan kills seedlings (Pre-emergence)
1. Application: am I using it for the right crop?
2. Concentration: do I need to dilute this stuff? how much?
3. Frequency: how often should I use it?
4. Conditions: when and in what weather do I apply it?
(don't spit into the wind! be ready to drink what you spill!)
5. Residue: how long will the plant be poisonous? when can I harvest? can it be washed off?
6. Uptake: is this chemical taken into the plant, making it toxic? (Systemic)
7. Duration: how long before my environment is pesticide free?
Can I grow a different crop here next year?
8. Biological Magnification: effect on "food chain" = DDT
Monocultural disadvantage - lost disease/pest resistance
Pest control costs
Disease/Pathogen (altered physiology or development)
Parasite on Host (decreased vigor)
Herbivore/Omnivore (plant parts missing)
General Ideas for Avoiding Pests
1. Buy resistant Varieties (T V F N Tomatoes)
2. Completely remove diseased/infested plants or limbs
3. Increase air movement and decrease humidity (Pruning!)
4. Optimize Growth: ALL FACTORS!
-Parts missing = chewing insect (bagworms, beetles, borers, cut worms, hornworms) or snail/slug
-Yellow/deformed leaves esp at top = sucking insect (aphids, nematodes, mealy bugs, spider mites, white flies, etc.)
-Discolored Leaves = fertilizer (maybe fungi NOT insects)
-Spotted Leaf/Fruit = bacterial, fungal, viral infection...maybe mites
-Collapse when watering is normal = fungi
Viruses-Tobacco Mosaic Virus - tobacco, tomato, potato, pepper, eggplant, petunia
-no curesBacteria-Tumors (Agrobacterium tumefaciens), Galls, Witches Brooms (Corynebacterium), fruit and blossom rots
-buy resistant varieties (T Tomatoes)
-keep smokers out of your garden, greenhouse
-antibiotics too expensiveFungi-molds, mildews, blight (mushrooms)
-keep plants in drier atmosphere
-fungicides work, but toxic to humans (Captan)PlantsBordeaux Mixture story = Copper Sulfate + LimeDogwood Anthracnose!
Sulfur Powder = Dust
Irish Potato Famine = thank a New World Plant and a fungus for the fact you are here-open plant to better air circulation
-buy resistant varieties (Korean Dogwood, VF Tomatoes)
-Parasites = Mistletoe, DodderAnimals-(Herbivores, Omnivores, etc)
-Weeds = Competitors (already discussed)-mechanical
Invertebrates (no backbone)Nematodes - nematicide (repel with marigolds?)Vertebrates - (backbones)
-buy resistant varieties (N Tomatoes)
Molluscs - snails and slugs - moluscicide
Arthropods - mites - miticide (Lindane, Kelthane)- insecticide - insecticide
systemic: Isotox, Temik)
-disease BT = Bacillus thuringiensis
-sticky boards = yellow + grease +- pheromone
-predators "not all insects bad!"
(wasps, mantis, ladybug)
-pick off yourself (alcohol swab or squash)
-water spray under leaves (eggs explode via osmosis)
-soap improves it!
-smother with oil spray (be careful timing, etc. TOXIC TO PLANT)
-diatomaceous earth (bleed to death!)birds - puke spray for scout birds
- shiny ribbon, tinsel
mammals - rabbits, ground hogs, mice, deer, birds, (moles), humans!-fences make good neighbors (10' for deer!)
-traps (dead or alive? where to release?)
-poisons (pets, humans, beware!)
This page © Ross E. Koning 1994.
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Go to the Plant Physiology Information Homepage.
Send comments and bug reports to Ross Koning at koningre∂gmail⋅com.