problem apple tree (wooly aphids)

[craig1971]

have an apple tree that is badly infested with wooly aphids i have tried everything to get rid of them i used provado ultimate bug killer but nothing seems to get rid of them. The branches of the tree have gone gnarled and swollen i think the tree is beyond saving
if i chop it down and replace it with another tree can you get dwarf trees that are resistant to these blighters that wont get infested with wooly aphids???

[FB.]

The rootstocks MM106 and MM111 give the roots moderate resistance to woolly aphids, meaning less places for them to hide.
The rootstock M116 also has some resistance, but possibly not quite as much as the MM rootstocks.
The rootstock M25 seems to be intermediate; slight resistance but not moderate resistance.

The two MM rootstocks and possibly M116 also seem to give slight resistance to the scion.

Most dwarfing rootstocks are susceptible.

Some scion varieties have some resistance. I have - or should I say, had - a huge problem with woolly aphids but nowadays the varieties I grow are those which are less susceptible.

The following not-too-difficult-to-find variety list are those that seem to be the least troubled in my area*:


Beauty of Bath
Fiesta (Red Pippin)
Golden Delicious
Irish Peach
Jupiter
Spartan
Tydeman's Early Worcester

*
Woolly aphid strains and their preference for certain varieties may vary in different parts of the UK. If you plant Golden Delicious next to Bramley the woolly aphids will usually choose to attack the Bramley. But if you only plant Golden Delicious the woolly aphids will have no choice but to try to attack it - or look for another tree in a nearby garden!
However, when woolly aphids attack the varieties with some resistance, the woolly aphid colonies are usually much slower-growing and often die-out. Scarring of branches after an attack is also less with the varieties which show some resistance.

[FB.]

Oh - there are also some rarer varieties which seem to have some resistance, but as they're rare they can be hard to find or may need to be grafted to order with a year or two wait for delivery.