Parsley Root Aphids (Dysaphis foeniculus og D.apiifolia)
The fresh green and nice smelling parsley are beginning to show yellow leaves (Dysaphis)
Foto: Magnus Gammelgaard
The fresh green and nice smelling parsley are beginning to show yellow leaves.
In every vegetable garden the must be a lot of parsley!
This delicious herb is to be used in many courses. The picking is by it self a great experience, with the fresh and wonderful smell.
It is not odd, that we all would like to be able to fetch it, both in the summer- and winter seasons.
However there are a lot of pest's that can make life more difficult if we are growing parsley. One of them is the carrot fly (or more correct the larva from the carrot fly) another is the parsley root aphid.
Not very much has been written about this pest under Danish conditions, perhaps because it is no big problem for commercial growers. However I can be a problem in private gardens.
The symptoms normally begin in late summer, where the first yellow leaves are to be found.
Pulling up the stalks without the roots, normally you will not se the aphids. (Dysaphis).
Photo: Magnus Gammelgaard
If you examine the plants just around ground level, you often will se a vivacious activity from running ants. Those ants are feeding on "honey dew", the waste product from the aphids and they are protecting their suppliers from beneficial insects.
The aphids are without wings; greyish and covered with wax like substances. It is very practical to be water-resistant, when you are living near ground level.
If you are pulling the parsley op from the ground including the roots, you will be able to see the aphids.
Those greyish aphids covered with wax like substances, are easy to be seen near the ground level.
Photo: Magnus Gammelgaard
According to the literature root aphids (as many other aphids) should be changing host. This species changes from parsley to hawthorn. This means that a part of the life cycle wil take place on hawthorn.
If this really goes on in Denmark, I do no know for sure!
Because the aphids are living close to the ground level or just below, they often are difficult to be found by natural enemies. Also the ants are attacking any intruder, which are getting too close to the "milking cows".
Growing parsley in rows should be better than close together, because the aphids are more exposed to natural enemies.
When the aphids probably are able to live the whole year on parsley, it is a good idea to use crop rotation, so that parsley is not grown in the same places every year.
Parsley is in fact a good when it comes to attracting beneficial insects like syrphids etc., take a look at altrecept2.htm
Spraying in private gardens are normally not to be recommended and especially not in vegetables.
You are allowed to spray with a malathion product, but not closer to harvest than one week.
If you have serious infestation in the autumn, it can be an idea to sow parsley late in the summer, to have good supply the next season.
If you want to read more about aphids in general, please check out : bladluseng.htm
Other root Aphids:
Opdateret d. 20.1.2012