Archive for the ‘scale’ tag
Scale attack
While scale has always been a problem with the indoor orchids I grow it has only recently become an outdoor problem for me. Last Jan Tea scale made an appearance. I never liked those shrubs anyhow.
This winter I’ve been battling it on both of my magnolias. I am testing a systematic pesticide which goes strongly against my use of nonharmful pesticides, but I really don’t want to lose these trees and nothing else has worked so far.
While researching scale treatments I ran across Scale insects which is a site from the Systematic Entomology Lab, USDA which helps you to identify which type of scale you have by photo. Once you’ve identified your enemy, you can learn all about them. ( Keep your friends close, but your enemies closer as it were ).
The proper way to keep scale off your magnolias is to spray your magnolias, especially new leaves, in the spring with insecticidial oils. This is a much more environmentally friendly preventative treatment and one I have done most years. It’ll be done again this spring.
Tea Scale – what is it and what to do about it
When I was outside last month making my first spring pass in the garden I noticed a row of false hollies had leaves all turning yellow and brown. When you see yellow leaves on a plant the very first thing you should do is flip the leaves over and look at the underside. When I flipped the leaves over I found scale. Neem or orange oils are the preferred choices and you can find them at most nurseries. I use orange oil, but in a pinch any oil you have hanging around the kitchen will do just fine. Spray the bottom of the leaves thoroughly.
If only a small part of a plant is effected, prune off that branch and spray the underside of remaining leaves with oil. These plants are totally covered. So if the spray does not work after two weekly applications, I’ll cut them back to the ground and let them start over.
Tea scale was first discovered on tea plants in the early 1900s. Hollies, camellias, tea, olive and citrus plants are all known to be victims. The life cycle is between 45 to 65 days. We can get them year round here in Houston as well as in other warm climate areas. Usually they show up in the spring.
If you have constant problems with scale in your garden you might also consider a systematic pesticide. These are absorbed by the plant through the roots and deliver toxins to the scale. I don’t use systematic pesticides in my garden, but if you are constantly fighting scale you should consider them. They are available at your local plant supply place as well. ( see Control of tea scale using root absorbing systematic insecticides )
About the only good thing you can say about scale is that is doesn’t move. So you know where to find it when you come back with another round of toxins. Scale does have a crawler stage early on when it is first hatched. Once it finds a good location it settles in and forms a hard shell over itself. Almost all the scale you see are female.
