Battling Beetles
By Bob Vavrek, Agronomist
While most folks look to the sky for fireworks during the 4th of July holiday, many superintendents look to the sky for the emerging Japanese beetle adults. This pest has slowly, but steadily, marched west from New Jersey where it was introduced into the United States in 1916. Ten years ago there were more sightings of Elvis made in Wisconsin than sightings of beetles. Now damaging populations of adults and grubs are well established in the Lake Geneva area, in Madison, and turf injury has been documented as far north as Eau Claire. Beetles have been observed on a few courses as far west as the Twin Cities.

The adults feed on more than 300 species of plants. Two favorites are Linden trees and Norway maples, which happen to be heavily planted, and the Norway maples overplanted, on many golf courses in the upper Midwest. In fact, don't waste your money on a Bag-A-Bug trap to monitor the arrival of adults if you have a Little Leaf Linden on the course - this tree is a beetle buffet.

The grubs cause the most headaches on the golf course. They feed on turf roots and can cause a considerable amount of damage when the population density exceeds 5 to 10 grubs per sq. ft. Irrigated turf can accommodate more grubs than unirrigated turf. Skunks, raccoons and opossums cause even more damage when they rip apart sod at night to feed on grubs. Once they locate an abundant source of grubs they will return to feed night after night.

The adults seen during July lay eggs in the soil that will hatch into tiny grubs in about two weeks. Adequate soil moisture is required for the eggs to hatch. If the soil dries out the eggs will die. Consequently, the presence of abundant adults does not necessarily result in abundant grubs. Plenty of adults were seen on trees and fairways at courses in the Detroit area this second week of July.

Use a cup changer to monitor the turf for grubs starting in early to mid August. Remember, healthy, irrigated turf can accommodate more grub feeding than sites without irrigation. A variety of insecticides are available to control a potentially damaging grub population. The key to success is to ensure the treatment reaches the target, so follow label recommendations carefully. Small grubs are always easier to kill than large grubs and early detection can spell the difference between successful control and failure.

This is old news to those who have had to deal with devastated turf in the past. Superintendents unfamiliar with Japanese beetles can be taken by surprise when this pest migrates into new territory. One course in central Wisconsin discovered they had a massive infestation early last September when the rough mower slid down the bank of a steep mound taking a large strip of turf with it. Without roots the turf was little more than a throw rug on a waxed hardwood floor.

No need to panic when beetles move into your area. Various universities have spent years studying the biology of Japanese beetles and ways to control this pest. Learn how to identify the grub and become familiar with its life cycle. With this knowledge, and a sound monitoring program, you will have little trouble battling beetles.

Source: Bob Vavrek, rvavrek@usga.org or 262-797-8743



On The Road With The USGA
By R.A. (Bob) Brame, Director
 It seems that summer has finally arrived. For most of the region the third week in June brought more normal temperatures as the official summer season kicked-in. The question is will the weather stay summer-like? Most courses could use the increased play that warmer temperatures should bring.

Unfortunately, one of the lingering issues from the wet and cool spring is moss encroachment on greens. There are a number of courses throughout the region dealing with moss eradication. While we continue to have a number of options for desiccating moss tissue, there are still some who have not looked past the moss to the actual reason(s) it has encroached.

Three components of the maintenance program that should be comprehensively reviewed when moss encroachment is a concern are: the mowing height, soil chemistry (fertilization and pH), and upper profile porosity (aeration pore space). Inadequate aeration pore space continues to be the single biggest issue when moss encroachment occurs. However, low mowing and/or fertilization also may need to be addressed. Typically, fall is the best time to desiccate existing moss tissue. Seldom do golfers complain (it's more curiosity and concern) about moss encroachment, and slow fill-in makes attempts to remove moss during the summer a questionable risk.

Dollar spot disease activity has been on the increase over the last few weeks. In addition to utilizing adequate water as a carrier when applying a fungicide for dollar spot, a preventative posture to avoid inoculum buildup is important for good control.

Root depth and health in greens seen on recent visits has ranged from very good to very poor. At either extreme or somewhere in between, it will pay dividends to maintain consistency with foliar feeding over the next few weeks. Utilize a soluble fertilizer containing N, P, and K. A rate of approximately 1/10th lb. of nitrogen per 1000 sq. ft. every seven days has proven to work well; and in particular, if we experience a harsh summer. Now is the time to make any needed adjustments with spoon-feeding to better guard root depth and mass as the season progresses. Waiting until density thins will greatly reduce the value of utilizing soluble fertilizers applied through a spray tank.

The US Senior Open Championship was held at Inverness Club in Toledo, Ohio during the last week of June. An ovation is due Tom Walker and his staff for an outstanding job with course conditioning. Well done!

Keep us posted on concerns seen at your course as the season progresses. We are always available via phone or email. Equally, it's not too late to schedule a TAS visit.

Source: Bob Brame, bobbrame@usga.org or 859-356-3272