Spring Pre-emerge Application and Drought Considerations
By Bud White, director, Mid-Continent RegionJanuary 31, 2012
Many pre-emergence herbicides can prevent runners from rooting in the spring.
The drought in the lower part of the Mid-Continent region has persisted for so long now that virtually every aspect of golf course maintenance has been impacted. Superintendents are making major changes in their management programs to compensate for turf that has been weakened by the combination of prolonged drought stress and intense traffic thanks to a mild winter. One area that is particularly challenging is the task of weed control.
Most superintendents use a combination of pre- and post-emergence herbicides to keep the course as free as possible from noxious weeds. In normal years, when the turf is healthier, there are many choices when it comes to weed control. Weakened turf however, is more prone to injury from the herbicide. For example, some herbicides cause what is commonly referred to as “root-pruning”, a condition in which the root system is stunted. Another common side effect is the inhibition of the ability of stolons to send new roots into the soil as they spread across the soil surface. This is often referred to as “pegging down”. Fortunately, there are some pre-emergence products that keep such damage to a minimum. Unfortunately, they are expensive.
To help damaged areas recover as quickly as possible superintendents find themselves having to make a difficult judgment call. Applying a pre-emergence herbicide will reduce weed competition but carries the risk of additional damage to already weakened turf. Omitting the herbicide provides a safer growing environment for the turf unless the weeds take over. Should this happen, post-emergence herbicides must then be applied – a process that is also expensive and creates unsightly conditions as weeds die out.
A good compromise many superintendents choose is to apply the more expensive, safer pre-emergence products to high profile areas of the course where the turf must be carefully nursed back to health. They can use the less-expensive options in areas where the turf is healthier and more tolerant of the side-effects. And, they may not use a pre-emergence product at all in undamaged areas saving money in the process.
It is important to point out that there is not a simple answer to this issue. The severity of the drought is such that it may take years for some courses to completely recover – particularly those courses with limited budgets. Golfers can help in two important ways. First, avoid driving carts in damaged areas even if you don’t see a sign or rope. Second, be patient. Once the drought ends the turf will gradually recover with good maintenance practices in place. It just takes time.
If I can be of help with this or other turfgrass management issues please do not hesitate to contact me.
USGA Turf Advisory Service invoices were mailed out late January. Remember that May 15th is the deadline for TAS discounts. The early payment fee is as follows:
- Half-day -- $2400 with a discount of $600 if paid by May 15 ($1800)
- Full-day -- $3400 with a discount of $600 if paid by May 15 ($2800)
I want to encourage your club to pay prior to May 15th to receive the $600 discount. If you receive your visit prior to May 15th, it is necessary for payment to be made within 30 days of the visit invoice in order to receive the discount. You can download a TAS application at http://www.usga.org/course_care/turf_advisory_service/How-to-Subscribe
If you would like more information about a Turf Advisory Service visit, please call us at (972) 662-1138 or (firstname.lastname@example.org). I look forward to being of service to you and your course.