MSUE Pesticide Education Turfgrass Pest Management (Category 3A) Care of Turfgrass Chapter 2

MSUE Pesticide Education

Ecological Benefits of Turfgrass n Oxygen production n Reduced erosion n Pollutant absorption n Reduced leaching n Cooling n Pesticide degradation

MSUE Pesticide Education Turfgrass Disorders: Non-Pest n Improper species selection n Lack of air movement n Too hot, dry or wet weather n Too much or not enough nutrients

MSUE Pesticide Education Turfgrass Disorders: Non-Pest n Soil compaction n Competition from other plants n Excessive wear or traffic n Too much thatch

MSUE Pesticide Education Turfgrass Disorders: Non-Pest n Improper height of cut n Too much or little sunlight n Poorly maintained mower n Improper irrigation

MSUE Pesticide Education Turfgrass Disorders: Pest n Animal Pests n Insect Pests n Weeds n Disease Pests Pest problems are often the result, not the cause, of poor quality turf.

MSUE Pesticide Education Requirements for Healthy Turf n Water n Temperature n Sunlight n Soil organisms n Nutrients n Soil type and condition

MSUE Pesticide Education Water has the greatest influence on turf health and quality. Cooling takes place through transpiration. Without sufficient water, I’ll go dormant.

MSUE Pesticide Education Temperature & Climate n Cool season grasses: –Kentucky bluegrass, perennial ryegrass, fine fescues, tall fescue, bentgrass n Transition grasses: –Tall fescue, bermudagrass n Warm season grasses: –Zoysiagrass, bermudagrass, centepedegrass, bahiagrass

MSUE Pesticide Education Michigan is a cool - cold growing zone. Shoot growth greatest between 60-75F. Root growth optimum with soil temperatures between 50-65F.

MSUE Pesticide Education Temperatures above these ranges affect the entire grass plant. Respiration Photosynthesis = Energy Shortage

MSUE Pesticide Education Sunlight n Required for photosynthesis n Species and cultivar preferences n Most grasses require at least partially sunny sites

MSUE Pesticide Education Shaded turf

MSUE Pesticide Education Soil Types

MSUE Pesticide Education Soil n Soil is composed of: –Inorganic particles (minerals) –Organic matter (remains of organisms) –Water –Air –Soil organisms

MSUE Pesticide Education An ideal soil contains: 50% organic and inorganic solid particles, and 50% open space (soil pores). Pores are filled with water or air depending on soil type, drainage, and season.

MSUE Pesticide Education Soil Texture n Percentages of sand, silt, clay particles SandSiltClay

MSUE Pesticide Education Sand n Large particles & large pores –Limited water and nutrient holding capacity –Limited compaction –Rapid water infiltration

MSUE Pesticide Education Clay n Small particles & small pores –Compacts –Slow drainage & water infiltration –Holds moisture –Holds nutrients –Poor aeration

MSUE Pesticide Education Ideal Soil n Composite of soil particle sizes and organic matter with: –Good water and nutrient holding capacity –Good aeration –Resists compaction

MSUE Pesticide Education Soil pH n pH is a measure of soil acidity 1713 Very Acidic Neutral Very Alkaline 57.5 Range for turfgrass

MSUE Pesticide Education pH affects nutrient availability. Determine pH with a soil test. Use lime to raise and sulfur to lower pH.

MSUE Pesticide Education Nutrients n Nutrient holding capacity determined by % of clay particles and organic matter. n Nutrient levels constantly change in the soil.

MSUE Pesticide Education Even when you suspect turf is showing symptoms of nutrient deficiencies, soil testing is the only reliable method of diagnosis.

MSUE Pesticide Education Nutrients: Overview n Nitrogen (N) n Phosphorus (P or P 2 O 5 ) n Potassium (K or K 2 O) n Micronutrients

MSUE Pesticide Education Nitrogen n Used in largest quantities –Dry clippings are about 5% N by weight n Turf most responsive to N n Deficiencies: –Poor color, growth –Symptoms develop easily because N levels can change quickly

MSUE Pesticide Education Nitrogen n Periodic applications needed for good quality. n Do not exceed 1lb./1,000 sq. ft./appl. –Do not over apply nitrogen –Too much N = weak, lush turf n N can move and contaminate water sources

MSUE Pesticide Education Phosphorus n Important for: –Root development, maturation, seed production n Practically immobile in the soil –Few soils deficient in P n Deficiency: purpling of blades –Do not confuse with cold weather coloration

MSUE Pesticide Education Phosphorus n Can move with soil particles into waterways. –Stimulates aquatic weed growth n 50lbs./acre is adequate. n Except for new turf, apply only when indicated by soil test

MSUE Pesticide Education Potassium n Quantity used - second to N n Important for: –Roots, wear, and stress tolerance n Deficiency rarely visible –Yellow and dead blade tips n 3:2 ratio of N:K commonly used –Visual response: minimal

MSUE Pesticide Education Micronutrients n Used in small amounts –Iron, copper, manganese, etc.. n May be limiting with pH above 7 –e.g., iron deficiency –Iron applications provide short term benefits

MSUE Pesticide Education Soil Organisms n Contribute to organic matter n Aerate the soil n Process nutrients n Degrade pesticides

MSUE Pesticide Education Prevent chronic problems by carefully selecting and installing turfgrass.

MSUE Pesticide Education Select grasses suited to growing conditions and planned use. Many varieties of Kentucky bluegrass, perennial ryegrass and fine fescue are suitable for MI conditions.

MSUE Pesticide Education Grasses n Species and varieties differ in: –Appearance –Wear tolerance –Maintenance requirements –Pest susceptibility –Site tolerance

MSUE Pesticide Education Turf stands composed of several grass types are better able to resist pests and adapt to different environmental conditions.

MSUE Pesticide Education n Blend: –2 or more grasses of the same species F Glade + Bristol + Cheri Kentucky bluegrasses n Mixture: –2 or more different species F Kentucky bluegrass + perennial ryegrass

MSUE Pesticide Education Some fescue and ryegrass varieties contain a fungus that is toxic to insects chewing on the plant.

MSUE Pesticide Education Planting Procedures n Eliminate weedy perennial grasses –Quackgrass, bentgrass n Rough grade to correct slope n Amend soil if needed n Analyze soil –Adjust nutrients and pH

MSUE Pesticide Education Planting Procedures n Work soil to depth of 6 inches n Remove stones and debris n Smooth grade area n Apply starter fertilizer n Plant: –Late summer is best n Rake, mulch, water the seedbed

MSUE Pesticide Education Post-Planting Care n Watering n Mowing n Fertilizing n Pest management } Healthy Turf

MSUE Pesticide Education Watering n Amount and frequency depends on weather conditions. n Keep moist - NOT wet. n Decrease amount and frequency as roots develop.

MSUE Pesticide Education Mowing n Mow as soon as desired height is passed. n Keep blades sharp and properly adjusted. –Dull blades may pull up seedlings

MSUE Pesticide Education Fertilizing n A couple of weeks after seedlings emerge or roots develop, apply 1/2 rate of ratio fertilizer. n Be sure to include K. n Water in fertilizer to prevent burning

MSUE Pesticide Education Pest Management n Young turfgrasses can be sensitive to pesticides. –Delay applications until established –Use alternative strategies –If a pesticide must be used: F Check label for rates on newly established turfgrass

MSUE Pesticide Education Maintaining Turf n Requires: –Watering –Mowing –Fertilizing –Aerating –Dethatching –Pest management

MSUE Pesticide Education Management practices must reflect the needs of the grasses, site conditions, and use objectives. Excessive maintenance may be wasteful or damaging.

MSUE Pesticide Education Watering Too much? Too little? How often? When? Rainfall? Irrigation? Dormant? No consensus, no simple answers.

MSUE Pesticide Education The amount of water lost by transpiration and evaporation from the turfgrass stand. 1 inch per week

MSUE Pesticide Education No single irrigation method meets season-long needs of a turfgrass stand. Make adjustments to keep the root zone moist, not saturated. Daily, light irrigation (1/5”/day) has been shown to be effective.

MSUE Pesticide Education Irrigated turf

MSUE Pesticide EducationMowing n Height –2-3 inches for most turf –Mowing short... F reduces root growth & vigor F increases weed invasion n Frequency –No more than 1/3 removed per cut n Enduring drought –Increase height of cut –Mow during cool hours-not when wilted

MSUE Pesticide Education “Don’t Bag Them” Clippings do NOT contribute to thatch. Recycle plant nutrients. Keep pesticides on the lawn.

MSUE Pesticide Education When clippings are removed, fertilization should be increased by 25-50%

MSUE Pesticide Education Fertilization n Consider: –Species and varieties of turfgrass –Site conditions F Sun, shade, wet, dry, soil type, slope –Utilization of the site F Wear, utility, “picture perfect”

MSUE Pesticide Education Fertilizer Characteristics n Water solubility n Slow release n Synthetic or “natural organic” n Soil reaction effects n Burn potential n Fertilizer analysis –Complete:

MSUE Pesticide Education Fertilizer burn

MSUE Pesticide Education Fertilizer Burn n Don’t apply to wet or stressed turf n Apply evenly n Don’t spill n Use granules or pelleted vs. pulverized n Water-in soluble fertilizers n Use insoluble, organic forms n Apply no more than 1 lb./1,000 sq. ft. per application

MSUE Pesticide Education Clay soils drain poorly and easily become compacted.

Compacted soils Relieves compaction, stimulates root growth. Core aerators more effective than spike or slit aerators.

MSUE Pesticide Education Thatch n Exists between green vegetation and soil surface. n Tightly intermingled living and dead stems, leaves, roots. n A thin thatch layer: –Reduces compaction –Moderates soil temperature and reduces water loss

MSUE Pesticide Education Thatch n Too much - over 1/2 inch: –restricts water, nutrient, pesticide and air movement –may encourage disease & insect pests n High N and rapid growth may encourage thatch formation n Pesticide use may increase thatch

Compacted soils Thatch Reduction Coring and processing the soil back into the thatch is the best way to reduce thatch. Composted thatch

MSUE Pesticide Education Shaded Turfgrass n Satisfactory –rough bluegrass, fine fescue n Fair –tall fescue, perennial rye n Poor –Kentucky bluegrass n Varieties make a difference

MSUE Pesticide Education Shaded Turfgrass n Tree and shrub roots compete for water and nutrients. n Tree canopies = umbrella. n High humidity can increase disease. n Suggestions: –Trim trees, reduce fertility, use tolerant grasses, mow high, irrigate carefully –Plant ground covers