Recently, the agronomists in the Southeast Region had the chance to collaborate and review items of interest occurring in the region. Their comments are shared below:
Weeds, plant-parasitic nematodes and insect pests all have been hot topics of conversation during Course Consulting Service visits in the southern part of the region. Furthermore, bermudagrass mites recently have been encountered at three different golf courses in South Florida. As discussed in the article “A Witch’s Brew of Troubles With the Bermudagrass Mite”, bermudagrass mite is a pest problem that is often not recognized or misdiagnosed as traffic damage, drought stress or an infestation of an off-type bermudagrass. Due to their very small size and the fact that they primarily feed under the leaf sheath, bermudagrass mites are difficult to identify. However, the characteristic witch’s broom damage is a reliable means of diagnosing this pest problem. Bermudagrass mites are an imported pest from Australia and are being found more frequently at courses from the Carolinas to Texas. State extension service recommendations for insect pest control should be reviewed to determine insecticide treatment options. Unfortunately, a lack of truly effective treatments makes controlling bermudagrass mites very difficult. While not an option in every situation, lowering the height of cut and removing and destroying all of the mowing debris are recommended cultural practices for managing bermudagrass mite infestations. Also, make sure that areas affected by bermudagrass mites are being adequately fertilized and irrigated to aid the recovery process.
Mole cricket damage has become more common on recent Course Consulting Service visits. Generally, mole cricket damage is isolated but can occur in several locations. As such, spot treating with inexpensive, short-lived materials is usually recommended to control mole crickets. Soap flushes can help determine the type of mole cricket you are targeting and the most effective time to apply an insecticide. Recently, a soap flush at a course in Orlando revealed a few small mole cricket nymphs and egg-bearing females. The eggs within the female mole crickets were still flat, soft and a yellow-green color, suggesting that the female was not ready to lay eggs. When 50 percent or more of the eggs become hard and BB-like, female mole crickets will lay their eggs in approximately one week. Once laid, mole cricket eggs typically take several weeks to hatch. It is best to schedule applications of long-residual insecticides around egg hatch to get the most efficient and long-term control of mole crickets. For more information on soap flushes and mole cricket identification see the following video:
For the first time in many years, it appears bermudagrass winter damage happened in North Carolina. Bermudagrass injury on fairways, roughs, and tees has been reported in Hickory, Greensboro, Durham, Raleigh and Winston Salem, among other cities. Damage predominately occurred on north-facing slopes, poor-draining areas, high-traffic areas and shaded areas. Hopefully the rhizomes in damaged areas are still alive. Digging underneath the soil to observe rhizomes in damaged areas will provide good information about recovery potential. Patience will be needed as many damaged areas hopefully will recover from rhizome regrowth over the next 6 weeks. TifGrand collars and approaches at a recently visited golf course were completely brown except where turf covers were used. New, cold-hardy bermudagrass varieties that are far superior to Tifway are now available in the Southeast Region, including Latitude 36 and Northbridge that were developed at Oklahoma State University with assistance from the USGA Research program.
A busy schedule of Course Consulting Service visits has generated several observations:
• Herbicide Resistance – Many courses have come to the realization that after many successful years using sulfonylurea herbicides to control Poa annua, large populations of Poa annua plants now are resistant to this class of herbicides. Herbicide resistance is particularly troubling on bermudagrass putting greens, where resistance plus the loss of Rubigan® leaves superintendents with few choices for controlling Poa annua.
• Aeration Season – Spring core aeration is now complete at most golf courses with bentgrass putting greens. Core aeration of bermudagrass putting greens typically begins in June or July. It is always good to see new roots growing down into aeration channels.
Information on the USGA’s Course Consulting Service
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