Summer Prep is Underway

PREPARING FOR THE HEAT

By Darin S. Bevard, director, Mid-Atlantic Region
June 11, 2014

The use of knife tines to vent the soil profile is one practice to help putting green grasses survive summer stress. Venting is beneficial to turfgrass health and minimally impacts playability. Do not be surprised to see a similar practice performed on the greens at your golf course.

Weather conditions have been favorable for cool-season turfgrass growth, but preparations for the inevitable summer heat are well underway.

In our recent travels, compliments about overall course conditioning have been heard frequently. Seasonal temperatures and sporadic rainfall have allowed firm, fast conditions to be produced and maintained without risking the health of cool-season grasses. Equally as important, temperatures have been warm enough to provide rapid improvement of bermudagrass tees, fairways and rough. It is one of those rare periods of weather in the mid-Atlantic region when just about everyone is satisfied regardless of the grass they are growing. Inevitably, temperatures will heat up and maintenance practices will become more conservative, especially on putting greens. Different strategies are available to preserve the health of the grass during high-stress periods.

• Venting. Poking small holes in the soil profile with a spiker attachment, solid aeration tines, or slicing tines can stimulate rooting, improve air exchange and help with water infiltration. These small holes can help the grass survive difficult environmental conditions during the summer. Frequency varies from weekly to monthly depending on individual circumstances. Disruption to playability is minimal and full recovery usually occurs in two or three days. 
• Smooth Rollers. Putting green mowers have the option of smooth rollers or grooved rollers. When grass is not growing aggressively, grooved rollers can actually create stress, especially under wet conditions. Smooth rollers should be considered under stressful conditions. This subtle change can alleviate stress on the grass. The use of smooth rollers leads to an effectively higher height of cut further reducing stress on the grass but also reduces putting green speeds. Under environmental extremes, the health of the grass must be considered before green speeds. Switching to smooth rollers is not a necessity, but it can be beneficial to turfgrass health. 
• Cutting Height. Raising the cutting height also reduces stress on the grass. With more leaf tissue on the plant, photosynthesis–the production of food–occurs at a higher rate. Increased photosynthesis helps the plant build up carbohydrate reserves to better withstand summer stress. Again, increasing height of cut leads to slower greens, but plant health must be considered before green speed during stressful periods. 
• Growing Environment. It may be a little late to make effective changes now, but at least evaluate the growing environments around your greens during the summer. It is no coincidence that the same greens struggle each year, and if nothing is done to improve growing environments the greens will continue to struggle. Compromised sunlight penetration and poor air movement lead to weak grass. Make plans now to take the necessary steps to give the grass the best chance of survival by removing trees and underbrush that negatively impact turfgrass health. Installing fans to create artificial air movement should be considered when air movement cannot practically be improved by removing trees and underbrush.

Our mid-Atlantic summers always seem to provide some challenging weather periods. Enjoy the current weather patterns as long as you can but don’t forget to prepare for summer stress. Understand that certain strategies are implemented to preserve the health of the grass at the cost of green speed. Tolerating greens that are a little slower in the short term while environmental stress is high will be beneficial in the long term.

Source: Darin Bevard (dbevard@usga.org)

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