Q: I have two black walnut trees close to my house. I need to get them taken down and I wonder if there are avenues available to sell the valuable lumber. Tim Thompson, Cartersville

A: My mother thought the same about a black walnut tree on our property. But although walnut lumber is expensive to purchase, it is not usually harvested from backyard trees. Your trees probably have several branches within 10 feet of the ground. This makes the lumber from the tree undesirable due to the limb defects. In addition, the trees might have nails, wire or even bullets embedded in the trunk. Sawmill owners do not want to risk their thousand-dollar blades on trees that aren’t clear of metal. I have more details at bit.ly/GAsellwalnut.

Q: Why do Joro spiderwebs always seem to have a smaller, second spider that is not as colorful as the larger one? Carol Roberts, Duluth

A: That is the dude spider. He is keeping slightly out of reach, waiting for a chance to have sex with the female. Interestingly, there is a scientific reason he is smaller. Scientists have shown that his small size allows him to travel farther by ballooning, using a thread of silk to catch a breeze and move quickly between webs and potential mates. On the other hand, the female spider’s larger size allows her to produce more eggs and offspring. Nature is fascinating!

Q: In the past, I have followed the March 1 and Sept. 15 rules for applying preemergent to my lawn. This year, I decided to use the soil temperature from georgiaweather.net as my guide. But even in late September, it still registers above 70 degrees. Am I doing something wrong? Sam Cannella, Dunwoody

A: You are doing it right! Soil temperature at the 2-inch depth is the gold standard for determining when to put out preemergent. To be sure you are doing it at the right time, soil temperature should be 70 degrees and gradually falling. That is the case in Dunwoody, so bring out your spreader and have at it!

Q: Did I hear you say that it’s OK to prune anytime you want to and if it bothers you, remove it? Kippy Hays, east Cobb

A: That is pretty much the gist of it, within reason. I think I was referring to declining trees, such as dogwood or spruce. Once they start down the slippery slope of decline, nothing can reverse the inevitable. Folks ask me how to cure a dogwood tree that is already 3/4 dead. My stock answer is to enjoy the blooms but there will come a time when the tree’s dead limbs will outweigh their sparse flowers.

Walter’s email address is georgiagardener@yahoo.com. Listen to his comments at 6:35 a.m. on “Green and Growing with Ashley Frasca” Saturday mornings on 95.5 WSB. Visit his website, www.walterreeves.com, or join his Facebook Page at bit.ly/georgiagardener, for his latest tips.