RE: aphid infestation

Spraying aphids with a hose off fruit trees would be like Sisyphus
rolling stones uphill.  In mild climates, adult females reproduce
asexually, giving birth to live offspring (often 12/day or 80/week) with
those offspring reaching adulthood within 7 to 8 days!  Unless you get
every one, you will have more the next day.  If one had a single rose
bush with a mild case, spraying might be practical- I manage one rose
early in the year this way.  However, a mature tree will not likely be
killed by aphids, though the honeydew they generate may be bothersome
and you may get some leaf-rolling.  Have you noticed whether you have an
associated ant infestation farming these buggers?  If so, you can slow
things by wrapping the bases with brown paper coated with "Tanglefoot".
Also remove any ant access where branches are touching fences and
providing access to the ground. Although you want to maintain an organic
atmosphere, ant stakes can be used to control the ants without affecting
any other insects, they take the bait as food back to their nests
affecting only other ants down there.  Be assured that any non-organic
spray control for the aphids or ants will affect beneficial insects as
well. Soap, neem oil and parafinic oils applied thoroughly with a strong
spray, coating all surfaces will control aphids present on the day you
spray and won't harm beneficials that fly in the next day.
On fruit trees, your best bet is a well-timed spray of oils applied as a
delayed dormant spray just as aphid eggs are hatching in early spring.
My brother Kurt has had problems with his fruit trees.  Perhaps he will
weigh in on the subject.

Karrie Reid
Folsom Foothill Gardener

-----Original Message-----
From: owner-medit-plants@ucdavis.edu
[o*@ucdavis.edu] On Behalf Of Diane Whitehead
Sent: Saturday, July 15, 2006 11:31 PM
To: medit-plants@ucdavis.edu
Subject: Re: aphid infestation

Anna,

   The emergence of aphids from wherever they hide is one of the sure 
signs of spring for me, on seedlings and new growth on my greenhouse 
plants. I squish them carefully, though sometimes I wonder whether my 
fingers actually do more damage than the the aphids were doing.

I don't notice many aphids in the summer,  though today I noticed 
some on a rosebud as I was watering, so I sprayed them off with the 
hose.

Could you spray your infested trees with plain water?

I just did a Google search for birds that eat aphids, and several 
people reported goldfinches cleaning all the aphids off their roses.


-- 
Diane Whitehead  Victoria, British Columbia, Canada
maritime zone 8
cool mediterranean climate (dry summer, rainy winter - 68 cm annually)
sandy soil
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index