The pathogen that causes Take-All Root Rot, Gaeumannomyces graminis var. graminis is always present in our warm- season turf species. Any type of stress can trigger this disease. Prolonged periods of heavy rainfall also encourage its development. In South Florida, we see the disease during summer and into the fall, so you’ll want to take proactive measures now. Symptoms present themselves on the leaves in the form of irregular, light- colored patches and eventual death of the turf. Take-All Root Rot can also be detected through inspection of roots.
One the disease develops, it is extremely difficult to control. The best management option is to prevent this disease from developing. This includes cutting no shorter than University of
Florida- recommended, species-specific mowing heights, never removing more than 1/3 of the blade, and taking care not to overfertilize, overwater, or otherwise stress the turf. For management, we recommend using a fungicide that contains pyraclostrobin, myclobutanil, azoxystrobin, triadimefon, fenarimol, propiconazole, or thiophanate methyl. It is best to use these fungicides preventatively, about a month before we normally see symptoms,which is right now. After the disease has begun to develop, these fungicides can be used, but field trials haven’t been conclusive as to which, if any, are most effective.
To help the turf make up for lost nutrients being delivered to the blades, a combination of slow-release and foliar fertilization can be used.
More information is available:
Photo credits: (1) William M. Brown Jr., Bugwood.org (2) Holly Thornton, University of Georgia, Bugwood.org
This three-part, Florida-Friendly landscaping workshop series begins on Monday, April 25th. The nine principles of Florida-Friendly landscaping will be covered over the three sessions. Emphasis will be placed on designing and managing a low-maintenance landscape with minimal water requirements. Please click on the image to view the full-size announcement.
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Florida Extension is a partnership between the University of Florida and Florida A&M University to improve the quality of life for people like you through education. In the coming decade, decisions will be made by Florida Extension that influence you and your community.
We invite you to participate in our Community Input Survey as a way to give your opinions about certain issues that may impact these decisions. The focus of this survey is your own community – where you live, shop, work and play.
The survey runs April 1 through August 19, 2011. The results of the survey will be available on the Florida Extension web site late in the year.
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The common name for the gumbo limbo spiraling whitefly has been changed to the rugose spiraling whitefly. This has been officially approved by the Entomological Society of America, but will be on their website for comment for 30 days.
First discovered in 2009 in Miami-Dade County, the new whitefly is easily distinguishable by its large size and the distinct spiral pattern in which it lays its eggs. It has a rather broad range of host plants, such as Gumbo Limbo, Mango, Coconut Palm, Live Oak, and Wax Myrtle, among others.
Rugose Spiraling Whitefly- previously Gumbo Limbo Spiraling Whitefly. UF Laura Sanagorski
Positive identification of the insect paired with symptoms such as presence of sooty mold, general plant decline, defoliation, and dieback may indicate an infestation. Much research remains to be conducted on this new pest; current management options are similar to treatment of other whitefly species in the landscape. Horticultural oils and insecticidal soaps can be used if the pest problem is small or detected early. Insectides in the Neonicotinoid or Pyrethroid families are effective for large-scale applications and severe infestations. Further information is available: