OSU Extension: What happened to my lawn?
With this stretch of hot days and spotty rainfalls around the county, many homeowners are all asking the same question, “Is my lawn really dead?” Check it out, in some cases, the upper portions of the turf may be dead but the crowns may still be viable. Pull up a few plants and tease apart the crowns at the base. Healthy but dormant tissue will be white and succulent; new green growth may be present. Dead crowns will be brown, and straw-like throughout.
Dormancy in the lawn
Turfgrass plants need soil moisture to sustain normal growth and development. The water use rates of cool-season turfgrasses during the summer period will often exceed the rate which natural rainfall returns water back into the soil. Once the soil moisture reserves are nearly depleted, the turfgrass will begin to wilt. This condition is evident as the turfgrass turns from green to either bluish-green or gray-green. Wilt is a sign of water stress and is usually most evident during mid to late-afternoon periods. A period of continual water stress that limits or prevents the growth of plants is termed drought. Once drought conditions develop, the lawn will stop all growth and development and proceed into dormancy.
Dormancy is characterized by the development of brown turfgrass. The turfgrass is not dead but instead in a condition to preserve the vital parts of the plant. By becoming dormant, turfgrasses reduce water usage and can concentrate the limited amount of available moisture into the crown, rhizomes and roots. This dormant condition will allow the turfgrass plant to survive adverse conditions for extended periods until soil moisture reserves are replenished. The length of time lawn grasses can survive in a dormant condition is contingent on a number of factors including soil moisture levels, daytime temperatures, condition of the turfgrass at the onset of dormancy, etc. In general, turfgrasses can be expected to survive in a dormant condition for up to 4 to 5 weeks with limited damage if temperatures are at or below normal. If daytime temperatures are elevated (mid-80s or higher) consistently through the stress period, only 3 to 4 weeks of survival should be anticipated. Dormant grass is lost once the crowns, rhizomes and roots begin to dehydrate.
Squash vine borer
The squash vine borer is a key pest of summer and winter squash, gourds and pumpkins. It is also seen in cucumber, gourd, and melon in Ohio. Unfortunately, it is usually noticed only after it has done its damage. Symptoms appear in mid-summer when a long runner or an entire plant wilts suddenly. Infested vines usually die beyond the point of attack.
Sawdust-like frass near the base of the plant is the best evidence of squash vine borer activity. Careful examination will uncover yellow-brown excrement pushed out through holes in the side of the stem at the point of wilting. If the stem is split open, one to several borers are usually present. The caterpillars reach a length of 1 inch and have a brown head and a cream-colored body.
The adult squash vine borer is a stout dark gray moth with 'hairy' red hind legs, opaque front wings, and clear hind wings with dark veins. Unlike most moths, they fly about the plants during the daytime, appearing more like a paper wasp than a moth.
This insect overwinters as a full-grown larva or a pupa one to two inches below the soil surface. Adult moths begin to emerge about the time the plants begin to run, and moth flight continues through mid-August.
The small brown eggs, laid individually on leaf stalks and vines, hatch in seven to 10 days. The newly hatched larva immediately bores into the stem. A larva feeds for 14 to 30 days before exiting the stem to pupate in the soil. There are 1 to 2 generations per year.
Management - The key to squash vine borer management is controlling the borers before they enter the stem. Once inside the vine, insecticidal control is ineffective. Poor timing of sprays is the usual cause of inadequate control. Very early signs of larval feeding indicate that other eggs will be hatching soon. Use two insecticide applications 7 days apart to control newly hatching larvae and continue to monitor for additional activity. Sprays need to penetrate the canopy to cover the vines to be effective.
Home gardeners may have some success with deworming the vines. At the first signs of the sawdust-like frass on vines, slice lengthwise near where the damage is found and remove the borers. Cover stems immediately with earth. Sanitation is also important. Vines should be removed from the garden and composted after harvest is complete to prevent the remaining borers from completing development. Burying a few nodes along each vine will encourage rooting at these nodes. This will lessen the impact if squash vine borers girdle the base of the vine.
Of course, always read and follow label directions for the safe use of any pesticide.
Watering the garden just right
Most garden plants will need 1-1.5 inches of water per week to maintain healthy leaves, flowers and fruit. When Mother Nature does not provide enough, it’s up to the gardener to supply the rest. Not too little, not too much, but just right!
When you do need to water, it’s best to do a thorough deep application, and then put the hose away for the rest of the week. The worst thing you can do to your garden is to sprinkle lightly every day. Frequent, shallow watering only moistens the upper layer of soil, which encourages plant roots to stay shallow. In turn, that top layer of soil dries out quickly, making shallow-rooted plants more susceptible to drying. This holds true for lawns as well as garden and landscape plants.
It is also possible to kill your plants with kindness. Overwatering occurs when soil is kept too wet for too long, forcing valuable oxygen out of the soil. Oxygen is just as crucial to plant health as water. When heavy rains fall, or thorough irrigation is applied, don’t water again until the soil begins to dry. While you don’t want the soil to become so dry that plants begin to wilt, it is important to allow air to occupy some of the pore spaces in the soil between watering.
Any newly set plants will need to be watered more frequently until they have a chance to establish new roots. Young vegetable or flower transplants may need to be watered every day or two, especially if the weather is sunny, hot and/or windy. Newly planted trees and shrubs may also need to be watered more frequently. But as the new plants become established, try to cut back on the frequency of watering.
Many plant fungal diseases are spread by splashing water during rain or irrigation. Drip or trickle irrigation will deposit the water low to the ground, keeping foliage dry; this is the most efficient way to deliver water only where needed. If watering must be overhead, try to water in the morning to promote quick drying and reduce loss due to evaporation.
SOURCE: Purdue University Consumer Horticulture
Food Preservation Safety
With many vegetable gardens in full production now is this time many folks begin to think about food preservation. Did you know you can have your dial gauge canners tested at OSU Extension in Fairfield County? It is very easy to simply call for an appointment at 740-653-5419 and drop off your canner lid. It could be tested while you wait or you can return later and pick up at your convenience. It is important to check dial gauges for accuracy before use each year. Gauges that read high cause under-processing and may result in unsafe food. Low readings cause over-processing. Pressure adjustments can be made if the gauge reads up to 2 pounds high or low. Replace gauges that differ by more than 2 pounds.
Upcoming events
Let's Preserve Series – at Keller Market House, 134 S. Columbus Street, Lancaster. Are you planning to preserve summer produce? Join Shannon Carter, Family and Consumer Sciences Educator and Sandy Bohl, instructor, with Ohio State University Extension Fairfield County to learn more. Call 740-653-5419 to register
Dehydrating: Tuesday, Aug. 6, 6 to 7 p.m.
Canning Basics: Tuesday, Aug. 20, 6 to 7:30 p.m.
Let's Preserve Series at Wagnalls Memorial Library
Dehydrating Thursday., Aug. 8, 6 to 7 p.m.
Canning Basics (water bath/pressure) Thursday, Aug. 22, 6 to 7:30 p.m
Registration: Call Wagnall’s Memorial Library to register 614-837-4765Questions: contact Shannon Carter, [email protected] or 740-653-5419
This article originally appeared on Lancaster Eagle-Gazette: Hot days, spotty rainfall: What happened to my lawn?