Question:
We have a huge magnolia tree next to our driveway that's infested with scale and also needs pruning. The scale is excreting an excessive amount of sticky honeydew dripping on the driveway and cars. So, we need to do something but do not know what can be done at this time of the year.? Any idea who I should contact?Answer:
- I would contact an arborist. They're the industry professionals handling large trees' care and maintenance. You can find them online or in the phone book.
- That said, Magnolias can be pruned at this time of the year: however, spring would be a better time to prune just before the flush of new growth. Unfortunately, this tree sounds too big for you to spray, so I'd use a professional. I'd get several bids to compare the price to prune and spray the tree.
- If you could spray, the best treatment is Horticultural Oil applied in the early spring and late August when the insect eggs hatch as crawlers. This is how the problem spreads to other areas of the tree. The oil will smother the active and recently settled crawlers.
- Next, you could apply Bayer Advanced Tree and Shrub Insect Control. It's a systemic pesticide applied to the trunk area and absorbed upward into the tree. It kills the scale by contaminating the juices that the scale is feeding on.
- Protecting a large mature tree takes about three weeks or more, but it will continue to work for a year. So, an annual application will control the problem. Bayer Advanced Tree and Shrub Insect Control is available online at your favorite garden center.
Question:
We're having a shed built in our backyard. A slab is being poured over an apricot and plum tree that has been removed. The stumps are below the soil surface. If I leave the roots, will I have a problem with shoots growing through the cement and shed floor?Answer:
- . It's not necessary to remove all the roots. You should level the area and remove those roots in the area of the new pads. It will be difficult for roots to penetrate a cement slab as long as it's poured correctly. I'd be concerned with cracks, especially from earthquakes, so that you might pour a thicker slab than normal.
- Apricots and plums are budded on the same rootstock that is notorious for suckering, so I'd expect that suckers will appear in the open area beyond the pads.
- Right now, there isn't much you can do. You'll have to wait for new shoots to develop and then spot treat them with a herbicide or remove them manually. Which herbicide you use will depend on where the shoots are and the location of desirable trees and shrubs. I wouldn't be inclined to spray any herbicide on bare ground as it's not a very effective control.
- You'll need to be persistent as it will be a battle of attrition that you will win.