This common mold on mulch and lawns isn't a problem, but its name is rather unappetizing
Gardening columnist Don Kinzler also answers questions about when to plant apple trees in the fall and the cause of tree leaf scorch.
Q: Can identify what looks like some kind of mold growing in one of my flower beds? It just showed up this morning, and there are six clumps of this stuff, about the size of dinner plates. I haven’t watered for a few days so it shouldn't be from excess moisture. I’m also wondering if I should dig it out or not disturb it. — Beth S.
A: The circular growth has a very descriptive, but unappetizing name: it's called dog vomit fungus, because of its appearance. Although it looks like a fungus, the organism is classified as a slime mold, and it's fairly common on wood mulch, lawns and decaying wood.
When conditions are favorable, and food (decaying material) is plentiful, a circular growth, called a plasmodium, develops very rapidly, and it can become several feet in diameter. The color can be yellow, pink, brown, tan or white.
Dog vomit fungus is not harmful to humans or animals and it doesn’t harm plants, according to Clemson, Cornell and other universities. The slime mold can be left alone, and it will disappear fairly soon after first forming. Or it can be scooped up and disposed of. A spray of water will also dislodge the growth, making it quickly disappear.
These slime molds and fungi are important parts of nature, working to decompose dead or decaying material while releasing nutrients and compost-rich products back into the environment.
Q: Can we plant apple trees now, and what varieties would you suggest? — Pat and Mick C.
A: Fall is a great season to plant trees. If they’re installed in September, the trees will begin producing new roots which will continue through October until soil temperatures cool into the 40s. Although there won’t be new branch growth this time of year, the new roots produced this fall will give trees a head start versus waiting until next spring to plant.
There are many great apple cultivars well-adapted to Northern growing regions. Two different cultivars are necessary for pollination, either in your yard or a neighbor’s. Selecting a type that ripens early plus a later cultivar is a popular option.
Ripening in August are Hazen, State Fair and Kinderkrisp. September apples include Prairie Magic, Sweet Sixteen, Honeycrisp and Frostbite. Apples best left on the tree until October are Haralson, Haralred, Fireside, Connell Red, SnowSweet and Honeygold.
Other older, well-adapted types include Mandan, Wealthy, Wodarz, Wedge, Prairie Spy, Chestnut, Goodland, Norland, Red Baron and Duchess.
Q: The leaves of our young Ohio buckeye tree are all brown and crisp around the edges. Is this a disease, and do we need to spray anything? The leaves look dry, but we’ve been watering it. — Bob K.
A: The brown, crisp leaf margins on your young tree are symptoms of an environmental disorder called leaf scorch. On hot, windy days, leaves lose moisture faster than the root system can pump water upward, resulting in the scorched appearance of leaves or leaf edges.
Even though moisture in the soil might be plentiful, a tree’s root system only has so much power to replenish the tree’s water needs. During brutally windy, hot weather, water easily evaporates from leaves at a faster rate than the roots can supply.
Leaves affected by scorch will look unsightly for the remainder of the growing season, but in many or most cases will survive and thrive in future growing seasons. As young tree root systems become more developed, trees are less susceptible to leaf scorch.
If you have a gardening or lawn care question, email Don Kinzler, NDSU Extension-Cass County, at firstname.lastname@example.org. Questions with broad appeal may be published, so please include your name, city and state for appropriate advice.