Too much rain makes bad things grow
April showers may indeed bring May flowers, but a wet spring and early summer have also spurred growth of fungi and molds.
While some are not at all harmful, they can be, at best, aesthetically displeasing nuisances.
In lawn and garden areas, foul-smelling stinkhorns are popping up. These appear as stalks with slimy caps. Fortunately, they are not harmful and will wither on their own.
Slime mold appears as a foamy yellow growth. It, too, is harmless and will dry up and fade away.
Bird’s nest fungi resemble small cups or miniature bird’s nests. Their “eggs” (actually spore-containing periodioles) splash out and stick to nearby objects. While not dangerous, they can be a nuisance.
If bird’s nest fungi appear on a mulched area, loosen mulch with a rake to allow some drying out. Fungicides do not control this fungus.
While these lawn and garden fungi and molds are rather unpleasant, at least they are small scale nuisances.
The fungus that causes apple scab is creating larger problems on susceptible crabapple trees.
Apple scab appears as roughly circular, velvety spots on both sides of leaves. The spots move through a color range from olive green to dark green to brown.
Heavily infected leaves curl up, yellow, and fall. Badly affected cultivars may lose most of their leaves by midsummer.
While the early leaf drop does weaken trees, most will survive. However, they will be distinctly unattractive in their defoliated state.
Controlling apple scab with fungicides is not a practical option for home gardeners, partly because application must begin before bloom. Sanitation can play a modest role in control.
By cleaning up leaves as they fall, the severity of the disease next year may be reduced as the fungus overwinters on partially decayed leaves. However, by far the best control is to plant scab resistant cultivars.
A number of white-flowering crabapples offer resistance to apple scab. These include ‘Adirondack,’ ‘Bob White,’ ‘David,’ ‘Donald Wyman,’ Golden Raindrops, Harvest Gold, ‘Professor Sprenger,’ Red Jewel, Malus sargentii, and Sugar Tyme. Topnotch pink to red-flowering crabapples include ‘Adams,’ ‘Louisa,’ ‘Prairifire,’ ‘Profusion,’ and ‘Purple Prince.’