Question:
One of our large pine trees is dying. My next-door neighbor noticed it and said it could be due to a broken sewer line that occurred two years ago. There is a healthy tree about fifteen feet to the left of the dying one. What should I be doing to correct the problem?Answer:
- The answer to this problem is unclear, but I'd be surprised if the broken sewer line is the cause of the problem. The water damage would have shown up sooner.
- In the Bay Area, pine trees, particularly Monterey Pines, are dying from the stress caused by the droughts and Pitch Canker.
- The stressed trees are susceptible to bark beetles and other insects that carry the Pitch Canker Disease. Insects feed on the trees, releasing the Pitch Canker fungus that plugs the water-conductive tissues and causes lesions where sap collects and drips down the trunk.
- The disease starts in the older needle bundles. Excessive needles turn brown and drop while new growth develops at the tips. Next, we see dieback beginning in the lower part of the canopy as entire branches die.
- The dieback continues up the tree until it's completely defoliated. Unfortunately, there are no known chemical controls for this disease.
- Healthy trees will fend off the insects, so the disease is not an issue. So, I'd have an arborist come on site and evaluate the trees. They can advise you as to what can be done next.
- More information is available athttp://ipm.ucanr.edu/PMG/PESTNOTES/pn74107.htm
Question:
Please tell me the best time to control Crabgrass. I treat it every year, and it always comes back. Is there anything I can do without replacing my lawn?Answer:
- Now through mid-March is when a pre-emergent herbicide is applied for Crabgrass. They're used combined with a fertilizer, so you do two tasks at once.
- Scotts is one of several manufacturers of these types of products found at your favorite garden center.
- A pre-emergent herbicide for Crabgrass that prevents the dormant seeds on the ground from germinating. You would apply a different herbicide for the actively growing Crabgrass later in the year.
- I will assume you are using the right product at the right time. Your lack of success can only be from one other thing. You have some other weed than Crabgrass.
- Today, Crabgrass has been used as the universal label for all unwanted vegetation in a grass lawn.
- My primary suspect, not controlled by a crabgrass herbicide, is a perennial weed called Bermuda grass.
- Bermuda Grass is a mass of wiry stems that goes dormant or turns brown in mid-November through mid-March. It spreads rapidly with warm temperatures. These brown stems are apparent today.
- On the other hand, Crabgrass is an annual that dies out in cool temperatures. It disappears during the winter, leaving behind bare ground or spots where it was. This is a distinguishing characteristic that separates it from all the other suspects.
- Your first step is to determine what the problem is. The nursery professional at your favorite garden center is an excellent resource in sorting through possible solutions.