Large Magnolia Suffering From Major Scale Infection

Question From: Boston, Massachusetts, United States
Q: I live in Ottawa Canada and have a large magnolia suffering from a major scale infection for the very first time. I understand the systemic form of treatment is the most effective for such a large tree and infection. Would you recommend the use of Dimthoate and where can I purchase it? Many thanks in advance for your help. Louise

A: Louise, Pesticides are illegal for use in Canada, so I cannot advise you on sources or uses. The chemical is labeled as poisonous with a scull and crossbones here in the United States and I would recommend it only be used by a professional, if at all. I suggest you contact a certified arborist for an onsite inspection and treatment of your tree. Best And Happy Yardening, Nancy

Comment: Dear Nancy, Thank you for your prompt response. I have consulted an arborist who recommends the horticultural oil treatment. As mentioned my tree is very large and high and the infection is major. I have a 3 story house and the tree is higher. I am concerned that the oil treatment won' t be very effective and will be very costly given that it will have to be repeated a few times. I am aware the dimethoate is not available in Canada and was thinking of driving across to Burlington US to purchase it. Presumably one can follow the usage directions safely if available in your country. The alternative would be to cut it down and I hate to do that to such a nice tree. Best regards, Louise

Response: Again I cannot recommend products to you as they are outlawed in Canada where you will be using them. A simple google search may give you your answers. When using and product labeled as poisonous the applicator should wear registered equipment. Best Nancy