A: I don’t recall ever seeing or being asked about them in my 28 years as county agent, but you are the second person to ask and send me pictures this spring.
What you have growing in the yard is cancer root (Conopholis Americana). It can also be called squawroot or bear corn. It is a perennial, nonphotosynthesizing parasitic plant.
The plant looks like some kind of mutant pine cone or something out of a scary movie. It grows to about 4 to 8 inches tall. It consists of a thick spike of flowers. During late spring, this spike is cream-colored and hairless.
The root of this is a parasite on the roots of oak trees or its saplings. This parasitic plant is indifferent to light levels. It will grow in a well-drained site where the soil is not too compacted. It is definitely an uncommon plant that can grow in every state east of the Mississippi River and north into Canada.
I guess we just had the right weather conditions and rainfall for it to pop up this spring. It is not anything you need to be concerned about and will not harm the oak tree it is growing on.
LARGE PATCH DISEASE: I have seen and heard quite a bit about large patch disease in lawns this spring, particularly on zoysia.
This disease is most common in the spring and fall as the grasses are entering or leaving dormancy. Ideal day temperatures are in the 80s, with night temperatures in the low 60s or upper 50s. Symptoms of the lawn include irregularly shaped, weak or dead patches that are from 2 to 10 feet in diameter. Inside the patch you can normally see brown sunken areas. On the edge of the patch, a bright yellow or brown to orange halo is frequently associated with recently affected leaves and crown.
Large patch is favored by thick thatch, excessive soil moisture and poor drainage, too much shade which stresses the turf, and early spring and late fall fertilization. This is one of the reasons we don’t like to fertilize lawns too early in the spring.
Treating the lawn with a fungicide can help, but it’s too late this spring. Remember the temperatures I said it likes. Once we get into the hot summer temperatures the disease often goes away on its own.
At this point I would watch it closely, but keep a close eye on it this fall as it begins to cool down and apply a fungicide if it reappears and you feel it is needed.
A few common fungicides include captan (Hi-Yield Captan Fungicide), maneb or mancozeb (Hi-Yield Maneb Lawn and Garden), thiophanate methyl (Scott’s Lawn Fungus Control) and myclobutanil (Immunox).
Cultural practices are very important in control. Without improving cultural practices, you might not achieve long-term control with a fungicide. Use low to moderate nitrogen, moderate amounts of phosphorus and moderate to high amounts of potash. Avoid applying nitrogen when the disease is active. Water timely and deeply. Avoid frequent light irrigation. Allow time during the day for the turf to dry before watering again.
Prune, thin or remove shrub and tree barriers that contribute to shade and poor circulation, as these can contribute to disease. Reduce thatch if it’s more than 1 inch thick. Improve the soil drainage of the turf. Soil test and add lime if the report shows a low pH.
REACH SID MULLIS, THE DIRECTOR OF THE UNIVERSITY OF GEORGIA EXTENSION SERVICE OFFICE FOR RICHMOND COUNTY, AT (706) 821-2349 OR SMULLIS@UGA.EDU.