Mid-Atlantic Regional Update
The winter to spring transition in the mid-Atlantic is always sure to provide some interesting and often frustrating weather scenarios, providing several challenges to even the most seasoned turf managers. If you enjoy Scotland and San Diego, come to Maryland….you’ll see them both in the same week (fig. A). So far in 2017, a mild January gave way to an abnormally warm February followed by an abnormally cold March (average temperature in February was actually warmer than the average temperature in March). This stop and go pattern often mimics the infamous, yet dreaded beltway traffic. From an agronomic lens, this is a time of year when we pay close attention to Soil Temperatures, Growing Degree Days (GDD) and Plant Phenological (development) Indicators to help predict pest development as many of the aforementioned benchmarks coincide with pest activity. Examples will be briefly summarized below.
Fig. A: Source: The Weather Channel App
Spring marks a transition from the propagative end of certain winter annuals, such as certain types of poa annua and common chickweed and the beginning of summer annuals such as knotweed, crabgrass and goosegrass. Soil temperatures have been all over the map (fig. 1 & 2), but are now rapidly approaching (and holding around) 50°F, suggesting pre-emergent strategies targeting some of these common summer annuals are advisable. Two commonly used pre-emergent chemical approaches are Barricade® (Prodiamine) and Dimension® (Dithiopyr) herbicides. Always consult manufacturer labels and local representatives for best use rates and timing for your region.
Figure 1 Figure 2
Many of our common turf pathogens persist in soil/thatch layers over the winter months and resurface as temperatures begin to rise in the spring, bearing their unsightly symptoms. We have seen some of these symptoms, in particular from Waitea or Brown Ring Patch (fig.3) and isolated cases of Type II Fairy Ring (fig. 4) throughout the warm surges. These symptoms are the latent effect from the activity of the pathogen over a period of time. Several curative options are available for these two pathogens in particular, to include, but not limited to fungicides in the DMI, QoI, and SDHI classes. Although several classes may control a broad spectrum of diseases, proper application method can determine results. For example, Waitea Patch applications should be directed at foliage, while Fairy Ring applications should be watered in to target thatch/upper soil-root zone.
Figure 3 Figure 4
In the coming weeks, as soil temperatures increase to a range conducive for additional soil-borne pathogen development, we will focus more attention on preventative measures against Summer Patch, Pythium Root Rot/Dysfunction and Fairy Ring, to name a few. There are also a broad range of fungicide classes to target these pathogens, independently or in combination. Past history, local environment and potential for multiple pathogens to be targeted in a single application should be considered to determine the best control approach.
Many insect and root infecting parasitic nematodes will also become increasingly active over the coming weeks. For those targeting white grubs and caterpillars using Acelepryn® insecticide, the window will soon be opening to control these pests for the season using the 8 fl oz/A rate.
For those who manage Annual Bluegrass Weevil (ABW) and may be using Acelepryn as part of the Optimal Control Strategy , the Stage 2 Application will recommend a 12 fl oz/A rate to target early instar larvae. This stage generally falls in the latter part of April in the mid-Atlantic. You can follow www.weeviltrak.com for updates in your area. This application will also control white grubs and turf caterpillars for the remainder of the season. In the meantime, we will be targeting overwintered adult ABW using a pyrethroid such as Scimitar® insecticide at 10 fl oz/A or Chlorpyrifos (see manufacturers label for proper use rate), perhaps as early as the second week of April in the Northern VA/DC/Baltimore Metro area. We generally use Base 50 GDD models (beginning March 1) and Plant Phenological Indicators (commonly Forsythia) to monitor ABW Adult spring emergence. Due to an early blossom, followed by an extremely cold period of about 10 days in March, much of the forsythia is in an “abnormal” state (fig. 5&6).
Figure 5 - Forsythia (L) on 3.2.17 Figure 6 Forsythia (L) 3.29.17
Adult ABW and Black Cutworm Full Life Cycle of ABW
One final mention in the insect category will be to provide a B.O.L.O for Hairy Chinch Bugs, which have created some damage late the past two seasons. This is about the time of year they begin to emerge and prepare for their seasonal mating rituals.
Hairy Chinch Bugs - Image courtesy of Jim Kalisch, University of Nebraska Entomology.
Nematodes have commandeered some of the conversation the past two summers, particularly during the most stressful points of the season. If you have had a history of Nematode-related issues, sampling may be advisable in the near future to prepare for applications once soil temperatures approach 60°F. Targeting the 2-3” soil depth is most effective to control turf parasitic nematodes and can require more complex application methods. Consulting with your local Syngenta Territory Manager to develop a strategy can assist with your preparation from initial scouting and sampling on through to implementing control options.
It will certainly be interesting to see what turn will be next in the mid-Atlantic, so stay tuned for future updates from this region.
Sam Camuso – Territory Manager (MD/DC/NoVA)
About the author
Sam Camuso is a Syngenta Turf & Landscape Territory Manager located in the Northeastern US. You may also follow Sam on Twitter: