Bay Leaf Ailment?

[Mark Durham]

Please could somebody suggest why these leaves are so discoloured. Thank you in anticipation.

Mark.

[digthatchick]

It looks like some sort of leaf miner - found this that maybe of help - BAY SUCKER
The technical term is trioza alacris, the common name is jumping plant lice (or louse)! The first signs are of leaves curling around the margins. Parts of the affected leaves then turn yellow. Finally the leaves will turn brown at the edges. The leaves finally fall off. This is often not fatal to the bay tree but it certainly weakens the tree leaving it open to other pests and diseases.

The best treatment for Bay Sucker is to keep an eye out for signs of damage so that it can be treated early on. Look out for those yellowing leaves which will also be thicker than normal where affected. When they are noticed, pick them off and burn them. Spray the under sides of all leaves with a very diluted washing up liquid solution.

If the damage is more severe you need to understand the cause. The bay sucker is a tiny insect about 2mm long which over-winters in nooks and crannies, often in the soil surrounding your bay tree. Breaking up the surface of the very top of the soil surrounding the plant to a fine tilth will help expose the pests, especially in the winter.

In mid April the first generation of Bay Suckers will appear and these will feed on the sap of your bay tree. They then lay even smaller eggs on the underside of the leaves, almost invisible to the naked eye. They can often be seen more clearly through a magnifying glass. These eggs also feed on the sap increasing the damage. They multiply quickly and often three generations worth can be seen on badly affected plants.

One pesticide works reasonably well if applied early on, it is thiacloprid. Have a look on the internet for products which contain this pesticide. be aware though, that this is a systemic pesticide and it will therefore remain present in the leaves for a couple of weeks (consult the package instructions). The leaves should not be used whilst the pesticide remains.

[rana]

I have had a similar looking ailment for some years on a bay in the garden. Apart from being a tad unsightly the plant continues to grow strongly (I regularly have to cut it back) with no apparant detriment to the long term health of the plant.

[Mark Durham]

Thank You

Many thanks for your replies. Last night, in a cooking emegency, I used a couple of the less troubled leaves in a dish. Perhaps this was not a wise move!

[digthatchick]

I wouldn't think that would be a problem, remember it's been cooked.

I was doing a persons garden on Wednesday and her Bay tree had been caught by frost, it looked in a very sorry state, I hand picked off every brown leaf! Now it looks great and you can now see the new leaves waiting to grow.

[rana]

No problem, just use the unaffected leaves

[Snadger]

Probably what my bay tree is suffering from! Looks like i'll have to Nuke the sucker!