Question
I have a Thuja tree, potted and approx 2m tall. Shortly after I bought it, it developed clumps of small white gooey balls at the tip which I was told were lice and used a poison recommended by the garden centre. I treated it once more and it appeared to clear itself, so I thought! I was on vacation and left my trees in goods hands and it was treated once more with the same poison. Now I find that the tree is covered to the bottom in the lice with the top part turning completely brown. I have two questions - can I save the tree? and should I be reimbursed by the garden centre as I feel confident the tree was infected at the time of purchase. I have one other identical tree and this is not affected at all.  thanks for your help. Regards

Answer
I dont know what you used as an insecticide.  Sounds like it may have been scale insects.  They are hard to kill because it is hard to get product in contact with them.  However, I would use the following product to treat your tree. I would treat the plant with Bayer Advanced Tree and Shrub Insecticide.  This product is mixed with water and poured on the soil around the base of the plant.  It is taken up systemically and will kill the bugs within a week or so.  It also provides protection from reinfestation for up to a year. This product will get rid of the bugs for sure. Good Luck.