Why is my boxwood turning brown?
There are various reasons this may be happening. Winter burn and injury, boxwood blight, seasonal dryness, root rot, salt damage, animal urine, and various insect pests are all possibilities. Given the time of year and the weather we have had this summer and fall, I would guess the most likely culprit would be seasonal dryness, although some of the others, particularly boxwood blight, insect damage, or root rot could be possible.
Winter injury can be combated to a certain extent by applying an anti-desiccant spray. Boxwood blight, if present, will be manifested by dark leaf spots, black streaks on the stems, and rapid leaf drop. It can be treated with an anti-fungal product. Root rot is due to poorly draining would which suffocates the roots,
causing the entire plant to wilt and turn brown. Seasonal dryness can be best handled by a balanced watering program, deeper watering instead of more often and shallow. If animal urine is the cause, using a repellant, such as white vinegar, around the perimeter of the yard, but not on the grass or plants, may help. If insect pests such as leaf miners, boxwood mites, scale, or boxwood psyllids are best found by looking at the underside of the leaves and can be treated with neem oil or a similar product.
Will the shrub recover and come back from this? It depends on the cause of the damage. If the damage is surface level winter damage, recovery is possible with new growth. However, if the damaged areas are dead, diseased, or very badly dried out, then recovery is not likely.
How do I get rid of grass burs in my lawn?
The best way to get rid of grass burrs and nutsedge is to use a pre-emergent grass killer in late winter to early spring. Existing nutsedge can be treated with a post-emergent product which is the most effective on younger growth. Hand pulling is also helpful, but nutsedge has little bulblets under ground which will resprout, however vigilant hand-pulling can help a great deal, digging out the roots when possible. Dragging a burlap sack or a blanket over the entire area is another technique, as the rough fabric will catch the burrs to prevent reseeding. Another approach is to build a healthy and thick lawn by watering deeply, mowing higher, and fertilizing as needed, to help crowd out the nutsedge.
Is now a good time to trim dead branches off my oak tree?
This is not a good time for trimming oaks due to the possibility of attracting sap beetles that spread oak wilt disease. If the dead branches pose a hazard, it is acceptable to trim those branches. If the branches do not pose an immediate danger or the trim is merely cosmetic, it is better to wait until December to February. If any living branches are cut in the warmer seasons, the wound must be sealed within 15 to 20 minutes to prevent the beetles from arriving and spreading disease.
Readers can pose questions or get more information by calling 417-874-2963 and talking to one of the trained volunteers staffing the Master Gardener Hotline at the University of Missouri Extension Center in Greene County located inside the Botanical Center, 2400 S. Scenic Ave., Springfield, MO 65807.
This article originally appeared on Springfield News-Leader: Master gardener explains what to do if your boxwood is turning brown
