Turf Flashcards
Most important factors in maintaining good turf
grass type, mowing, watering, fertilizing, and thatch control
CO average elevation
6,800 feet
% of nations land above 10,000 feet that is in CO
3/4
cool season grasses
bluegrass, tall fescue, and rygrass
warm season grasses
bermudagrass, zoysia, and buffalograss
Diagnosing turfgrass problems
determine the kind of grass or grasses, find out why the problem occurred, determine solution, check the label for turf grass species and problem, and recommend good cultural practices
IPM Process
set economic thresholds, monitor and identify pests, prevention, and control
Pest Management Methods - Soil
Fertile soils with a pH of between 6 and 7 are desirable. Good drainage, adequate water, and oxygen. Modification by supplying amendments in small increments.
Turfgrass Selection
Cultivars (varieties). Plant mixes and/or blends.
Cultural Practices
Mowing, watering, fertilizing, and cultivating.
Biological Control
us of bacteria, fungi, nematodes, and parasitic or predaceous insects to control pest organisms.
Prevention and Sanitation
Plant grass/seed that is free from pests. Collect grass clippings to prevent further spread of weeds and disease.
Pesticide Selection
Application method and timing, toxicity, effectiveness, host specific, cost, persistence.
DF
Dry Flowables - form a suspension when mixed with water and require less agitation than wettable powders.
WDG
Water dispersible granules - form a suspension when mixed with water and require less agitation than wettable powders.
D
dusts
EC or E
emulsifiable concentrates - common liquid formulations of pesticides that have active ingredients that are insoluble in water. Include an emulsifier that allows them to mix with water. Milky
F
Flowables - only produced in solid or semi solid form. often ground in powder and suspended in liquid.
G
Granulars - no mixing
microencapsulated
mixed into a liquid.
SP, S, or L
soluble powders - dry. go into true solution when mixed with water. My be formulated as liquids.
WP or W
wettable powders - formulated on a dry particle and contain ingredients that allow the particles to mix with water. mixture becomes a suspension
Adjuvants
can reduce number of fine droplets and decrease drift, increase the effectiveness, or make application easier.
Sufactants
used to improve spread of spray mixture on foliage. good for plants with waxy or hairy leaves.
stickers
guard against rain or irrigation. improve weather ability.
synergists
block the ability of the insect from breaking down the insecticide.
penetrants
increase uptake of herbicides into a plant
buffers
decrease break down of the pesticides that occurs from exposure to alkaline water conditions.
Suitable tank materials
polyethylene, fiberglass, and stainless steel
tips most resistant to abrasion
tungsten carbide, ceramic
tips that do not resist abrasion
brass, nylon
aluminium
wears out quickly
controlled droplet sprayers
rotary spray nozzles - sprays in a hollow pattern. droplets fall nearly vertically onto the target.
low pressure sprayers
15-80 psi
Calibration of Equipment
- correct nozzel 2. clean and inspect 3. check gauges 4. check spray volume
Phytotoxicity
plant damage resulting from a pesticide application to a desirable plant
Transportation
movement of a pesticide away from its intended site of action.
Transformation
pesticide’s chemical structure is altered - usually desirable because they become less toxic.
Leaching
downward movement of pesticides and nutrients through the soil.
Soil Organic Matter
influences how much water the soil can hold before it begins to move downward.
Runoff
when precipitation rate exceeds the rate of water infiltration in to the soil.
Volatilization
when pesticide changes from a solid or liquid to a gas. occurs at vapor pressure for the specific pesticide. Increases with increase in temperature.
Amines
generally non volatile herbicides.
Esters
more likely to be volatile herbicides.
Particle Drift
movement of small spray particles away from the target area.
Absorption
movement of particles into a plant
photodecomposition
sunlight-induced transformation can be an important fate for some pesticides. alter the chemical properties of a pesticide, making it less toxic - and sometimes less effective.
microbial decomposition
most common means of pesticide degradation. action of microorganisms found in soil and thatch.
chemical degradation
the hydrolysis of pesticides (how pesticide react with water).
Persistance
measure of how long a pesticide remains in an active form at the site of application or int he environment.
Accumulate
when pesticides build up in the bodies or animals or in the soil.
Who needs to be licensed in turf?
those who apply pesticides to turf to control invertebrate pests. also anybody on private property that comes within a maintained area surrounding residential or commercial structures or within 50 feet of a residential or commercial structure
Written statements must contain
- state that pesticide has been applied. 2. pesticides applies. 3. date 4. precautionary statements from the label.
Posting signs regulations
- be within 2-5 feet of property boundary.
- water resistant.
- at least 4” high x 5” wide.
- the word “WARNING” in at least 60 pt bold-faced font type.
- words “PESTICIDES APPLIED” in at least 24 pt bold-face font type.
- Symbol of a circle at least two inches in diameter with a diagonal slash over an adult, child, and dog.
- name of the applicator who made the application, in at least 18 pt bold-faced font type.
- at least 18” above the ground and no higher than 48”.
Applications on Commercial Properties
if the applicator makes a pesticide application on a commercial property and the owner isn’t there, the sign must also have the following:
- telephone number of the applicator.
- name of the pesticide
- date the pesticide was applied.
Hazard
toxicity + exposure
LD 50
limited dose
LC 50
lethal concentration
Heat exhaustion
dry membranes, dry mouth, no tears, no saliva, fast pulse, fainting.
organophosphates/carbamates
moist membranes, salivations, tears, saliva, slow pulse, coma
Triazines
herbicides that are often formulated as emulsifiable concentrates and liquids.
Chlorophenoxy Herbicides
2, 4-D and mecoprop.
First Aid
- move patient away from source. loosen clothes to ease breathing. 2. check breathing. use CPR if no pulse 3. remove clothing and drench skin with water. clean with soap and water. dry and wrap in blanket. 4. Wash eyes for 15 min or more. 5. DO NOT induce vomiting unless the label says to do so, or the material is known to be very toxic. 6. if unconscious, give activated charcoal. 7. protect the patient from hurting themselves. 8. keep warm and quiet.
White Grubs
larval stage of scarab beetles or scarabs. lawn appears drought stressed or dying, usually in late summer or early fall. roots are clipped, and turf may roll up like sod. soil is loose. vertebrate pests are digging up turf. c shaped larva may be found. Treatments must reach the root zone. Larva have 3 legs.
Masked Chafers
Adults are shiny light-brown scarab beetles about 1/2” long with a dark mask across the head. Eat roots. Adults are sometimes resistant to pesticides. Best if treated while they’re young.
May and June Beetle
Common in eastern plains. 3 year cycle. Same as masked chafers for treatment.
Bill Bugs
weevils, snout beetles. Dead turf, does not respond to watering. Sawdust-like frass is produced. soil under turf is still firm. grass breaks easily at the crown. Larva have no legs. Treat thatch layer of turf.
Sod Webworms
“lawn moth.” thinning or failure of lawn to green up in spring. flocks of birds will feed on the lawn/moths. cupped leaves, or green frass (droppings). For treatment: mow lawn and remove clippings. apply pesticides late in the day.
Larger Sod Webworm
damage done by larva. adults do not damage turf grass.
Cranberry Girdler
caterpillars. orange head. adult moths are small. feed on grass roots, primarily in sept and oct.
Cutworms
cut plants at ground level. not very common. back cutworms can be a major pest to golf greens.
Clover Mites
smaller that the head of a pin. dark green with red/orange legs. Long front pair of legs. Reproduce when it’s warm. Feed on grass blades, which die and get a speckled appearance. Usually on S and W side and damage within 6 feet of building. Treat with miticides. Adequate water is needed to control clover mites.
Banks Grass Mite
smaller and lighter that clover mites. Green. No long front legs. Adequate water is the only control. Most difficult mite to control in turf grass.
Pathogens
biotic (living) entities that cause disease. Pass from plant to plant by vectors (anything that can transport the infection). Reproduce through replication, fission, or spores.
Viruses and Viroids
submicroscopic particles made of nucleic acid and protein. Take over cell metabolism and induce the cell to make more viral particles. Contained in living plant cells and can’t survive in the environment unprotected.
Symptoms of Viral Disease
Mosaics, ringspots, distortions, stunting, and necrosis.
Bacteria
single-celled, microscopic. have true cell walls and multiply by binary fission.
Symptoms of Bacterial Disease
leaf spots, blights, cankers, soft rot, wilt, and ooze
Phytoplasmas
bacteria-like organisms enclosed by a membrane instead of true cell wall. found in plant phloem (food-conducting tissue). Vectored by leaf hoppers.
Symptoms of Phytoplasmal disease
witches brooms, distortions, general chlorosis, necrosis, and leaf drop
Fungi
multicellular organisms with a filamentous vegetative state. Attack all plant parts.
Symptoms of Fungal Disease
leaf spots, distortions, stunting, wilting, damping-off, blights, necrosis, rots, and rusts.
Signs of fungal disease
mushrooms, mycelium, sclerotia
Nematodes
microscopic round worms. Feed on plant roots. severe damage may include yellowing of grass foliage. Can breakdown genetic resistance and open the way for other pathogens. Problems can be identified in the lab though soil and plant analysis.
Symptoms of nematodes
root galls, poor overall growth, yellowing of grass foliage, distortions, and stunting
Signs in nematodes
cysts
Parasitic higher plants
true plants that reproduce by seed. most have little or no chlorophyll so they obtain nutrients by parasitizing other plants. Others have chlorophyll but no roots so obtain water and minerals form their food source host.
Symptoms expressed by host of parasitic plant
stunting, decine, wilting, and yellowing
Environmental Factors
abiotic (non living) conditions that affect plants
Moisture imbalance
most frequent.
not enough water - appear stunted, pale, have few small drooping leaves, fail to thrive, wilt, and die. Marginal scorch is especially diagnostic
too much water - excludes oxygen from the soil. Upper portion of the plant turn yellow, wilt, and die.
Anaerobic organism
any organism that can survive without oxygen. Usually release substances into the soil that are toxic to plants
Nutrient Imbalances
low levels of nutrients in the soils combined with high soil pH - makes the nutrients unavailable to plants.
Macronutrients
nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S).
Micronutrients
iron (Fe), boron (B), manganese (Mn), zinc (Zn), copper (Cu), and molybdenum (Mb).
Disease Components
susceptible host, pathogen, and environmental conditions. disease triangle
Inoculation
coming together of pathogen and host
penetration
invasion of the host by the pathogen
infection
colonization of the host by the pathogen characterized by growth land reproduction of the pathogen and development of symptoms in the host
Dissemination
spread of the pathogen by active or passive means
Over wintering/summering
survival of the pathogen during unfavorable periods
monocyclic
take an entire year to complete
polycyclic
produce many times in a season
Select fertilizers that contain
N, P, K, and Fe. Nitrogen is the most important element
ammonium
decreases pH
nitrate
increases pH
average pH in CO
7.2-8.3
mowing height
2.5 - 3 inches. no more than 1/3 of the blade should be removed at one time.
biotic diseases and problems
fungus, thatch, algae, moss, dog urine
abiotic problems
compaction, soil type, fertility, water, heat stress
Ascochyta Leaf Blight
High N. large inform areas of straw colored turf. patchy. prevalent in wet spring. common in Kentucky bluegrass.
broad spectrum fungicide.
Pink and Grey snow mold
High N. kentucky bluegrass, fescues, and ryegrasses. bleached to rusty brown. occur during prolonged, cool wet weather.
cut grass short in fall. apply protectant fungicide. broad spectrum fungicide.
leaf spot and melting-out
High N. small dark purple to black spots not he leaf blade.
water grass deeply and early in the morning. reduce thatch. use resistant cultivars in new plantings broad spectrum fungicide.
Anthracnose
Low N. small yellow patches. mycelial mats and tiny black fruiting bodies with spines can be seen.
avoid P or K deficiencies. Light N application. Reduce soil compaction. Deep and infrequent watering. Systemic fungicides. no chemicals are available for basal rot.
Dollar Spot
Low N. light tan color on blade with reddish brown bands on either side. kentucky bluegrass, annual bluegrass, bermudagrass, fine-leaf fescues, perennial ryegrass, and zoysiagrass. Usually only an aesthetic problem.
raise N levels. water early in the day. raise mow height and mow often. Plant resistant cultivars. contact and systemic fungicides.
Fairy Ring
Saprophytic fungi feed on dead organic matter in the turf. Lush ring of green grass.
Aeration. Suppress with multiple applications of N. Remove buried organic matter, remove sod and fumigate soil. fungicides.
Necrotic Ring Spot
Bluegrass. Results from poor site prep, excessive management inputs, thatch, and poor water infiltration.
Use Core aeration, avoid excessive N. Overseed with resistant cultivars. Fungicides.
pre emergence herbicides
typically used for controlling annual weds and perennial weeds that start from seeds. Will not kill them after the seed germinates.
4 stages of growth
seedling
vegetative
bed and flowering
maturity
Annual Bluegrass
Winter annual grassy weed. apple green in color, with whitish-green seed heads at any mowing height. Dies in hot weather, leaving patched in lawn.
Mow as high as practical. apply pre emergent herbicides.
Common Chickweed
Winter annual broadleaf weed.
Aerate turf to control thatch. postemergent herbicides to control.
Henbit
Winter annual broadleaf weed. member of the mint family. Very difficult to control.
Aerate turf to control thatch. postemergent herbicides to control.
Barnyardgrass
Summer Annual Grassy Weed. coarse textured annual grass with purple sheaths that lie flat on the ground.
Mow as high as practical to limit weed seed germination. Pre-emergent herbicides 2-4 weeks before crabgrass seed germinates. Postemergent herbicides to young seedlings.
Crabgrass
Summer Annual Grassy Weed. Mow as high as practical to limit weed seed germination. Pre-emergent herbicides 2-4 weeks before crabgrass seed germinates. Postemergent herbicides to young seedlings.
Yellow Foxtail
Summer Annual Grassy Weed. Often confused with crabgrass until it flowers.
Mow as high as practical to limit weed seed germination. Pre-emergent herbicides 2-4 weeks before crabgrass seed germinates. Postemergent herbicides to young seedlings.
Goosegrass
Summer Annual Grassy Weed. Grow flat on the ground.
Mow as high as practical to limit weed seed germination. Pre-emergent herbicides 2-4 weeks before crabgrass seed germinates. Postemergent herbicides to young seedlings.
Sandbur
Summer Annual Grassy Weed. Barbed burs easily pierce the skin. Can be confused with yellow foxtail until burs appear.
Mow as high as practical to limit weed seed germination. Pre-emergent herbicides 2-4 weeks before crabgrass seed germinates. Postemergent herbicides to young seedlings.
Black Medic
Summer Annual Broadleaf Weed. Dark green and grows close to the ground. Legume family.
