Laura Simpson writes the Master Gardener column each week.
Q: We have an avocado tree that is more than 20 years old and over 20 feet tall. It gets sun mid-afternoon to sundown. The tree is located in between a grass lawn & an in-ground swimming pool. We have hundreds of medium to large (very delicious) avocados every year. The leaves are dry at the tip and have always been that way. However, this year the leaves have a strange color & weird “pattern.” I have attached pictures. What could this be? Is it possible the roots have created a crack in the pool & the chlorine is leaking?
One of your photos shows brown leaf tips, which indicates possible salt exposure. This could be due to our naturally dreadful soil, irrigation with hard water, or possibly exposure to water from the swimming pool.
The second photo shows leaves that are blotchy with yellowing between the leaf veins. The veins also appear to be reddish-brown in color. This may be due to soil or water conditions but could also be caused by mites or thrips. Look at the undersides of the affected leaves. Is there any webbing or dull residue? Use a magnifying glass and look for any tiny critters. Avocados are susceptible to several species of mites and thrips, but these are difficult to see without magnification. If there are mites or thrips present, they can be controlled by removing any stressors (irregular watering during hot weather) and washing any dust off the leaves. Don’t use broad-spectrum insecticides or miticides since this will kill off any predatory insects that can control the mite population naturally. If your tree is still producing good fruit, this may be caused by a minor mite infestation.
Q: A couple of years ago, you gave a remedy for getting rid of skunk smell. Could you reprint that since my dog has had a couple of close calls and I want to be prepared.
Healthy skunks are mellow creatures. I once approached one, thinking it was a neighborhood cat, and almost touched it before realizing it was a skunk (it was dark, and I was really tired). They will only spray if threatened, and will give ample warning by stamping its feet, turning its back to you, hissing and raising its tail. Most dogs, being social doofuses, will ignore all of these warnings and proceed to either try to play with or chase this interesting striped creature.
Of course, this is most likely to happen at night well after the pet supply stores have closed. Here’s the recipe for skunk scent neutralizer that can be made with common household ingredients.
1 quart 3% hydrogen peroxide
¼ cup baking soda
1 teaspoon (or more) liquid soap
Once the hydrogen peroxide is mixed with baking soda, it will fizz quite vigorously. Apply immediately to the dog and massage it into the fur. Take care to avoid eye contact. Rinse thoroughly and hope that your dog will remember not to mess with skunks again. Don’t save any leftover solution since it loses effectiveness quickly.
Los Angeles County
mglosangeleshelpline@ucdavis.edu; 626-586-1988; http://celosangeles.ucanr.edu/UC_Master_Gardener_Program/
Orange County
ucceocmghotline@ucanr.edu; http://mgorange.ucanr.edu/
Riverside County
anrmgriverside@ucanr.edu; https://ucanr.edu/sites/RiversideMG/
San Bernardino County
mgsanbern@ucanr.edu; 909-387-2182; http://mgsb.ucanr.edu
