Q: My silver maple trees have blotches and bumps on the leaves — some of them have just a few, some are just covered with them. Is this going to kill my trees? What should I do?
A: Below is an excerpt from E-56, Galls on Shade Trees and Shrubs (PDF 136K) from Purdue Plant & Pest Diagnostic Laboratory. I’m also including the link to E-56 that will give you the full explanation of “Galls” with pictorial examples.
“The silver or soft maple trees are often attacked by tiny mites that cause small, wart-like growths on the foliage. These growths are first red, and then turn green, and finally black. They occur singly or in clusters and may be so abundant that the leaves become crinkled, deformed and drop early. Once formed, the galls cannot be removed from the leaves because they are composed of plant tissue and are actually part of the leaf. Many homeowners become alarmed when they discover infestations of the maple bladder gall, fearing that their trees might die unless control measures are taken. This is not likely. The galls never cause permanent injury and have little effect on tree health and vigor. The galls do, however, detract from the normal beauty of the foliage.
The maple bladder gall mites overwinter in cracks and crevices of the bark. As the buds swell in the early spring, they migrate out on the bud scales. This is when mites are most susceptible to dormant applications of oil spray. When buds open, the mites feed on the newly developing leaves. In response to this feeding, hollow galls are formed. The mites then live, feed, and mate inside. In fall, mites move back to the bark to hide over the winter.”
I love gardening tips and recently heard a few that you might like as well:
• Lay your shovel on the ground. Lay a measuring tape alongside the handle and begin marking off inches and feet with a permanent marker. When planting bulbs or plants all of which require a certain depth, the handle works as your planting guide.
• Don’t discard those clay pots whether large or small. They are useful in the garden even if they are broken:
• Broken clay pot pieces can be used as you would stone or mulch of any kind on the soil in the garden or a container. If the pieces are too large, break them up with a hammer so they are any size you would like.
• If you have several, turn them upside down to form an attractive border around a planting bed.
• Use them along a walkway when you want to insert small flags for the 4th, maybe a holder for a decorative item on a stake for Halloween or Christmas — even a candle holder to light the path for a holiday party.
• Turn one upside down and insert the garden ornaments being offered today (many of which come on a metal rod) through the hole in the bottom and into the soil for extra stability and as an attractive base.
• These pots make great covers for tender plants when a frosty night threatens.
• I use twine for many things in the garden. Use the pot to hold the ball of twine then thread the end through the hole. No tangles and you can always find the twine.
• Use one or more of the pots for those small gardening hand tools you routinely need. If you have several duplicate tools, place them in convenient locations.
Jane Ford is an Advanced Master Gardener. Email questions to firstname.lastname@example.org. This column is the opinion of the writer and does not necessarily reflect the views of The News-Sentinel.