Japanese Maple Bark Split???

[fallgirl]

Hi Everyone,

I live in Toronto, Canada and we had a very cold harsh winter last year. We suspect this may be the problem with two of our maples but we are uncertain. The Maples were planted three years ago and for the first year we protected them with burlap throughout the winter. The last two winters we did not. One is a green lace leaf the other purple lace leaf. Both are planted in a raised planter box that is about 20 feet long x 6 feet wide and 3 feet deep approx. This spring the purple lace leaf only developed a few buds and never proceeded to get leafs etc. It developed a crack in the bark that started at the base of the trunk and ran up only about 1 foot. Both trees are small 3 feet tall x 3 feet wide, very low to the ground and were very very full healthy trees. We were instructed by our nursery to remove the cracked bark and to put Green Earth clear pruning sealer on in hopes to save the tree. We did this and it did not survive. This morning my husband has now noticed a similar crack beginning at the base of the green maple. We are very surprised as this is one healthy, very nice looking tree. The soil is excellent, sufficient water and sun exposure is only half day. He sees a lot of ants around lately but nothing overly suspicious around the tree. Any ideas to help us save this one?

 

[Elmore]

Can you post some photos?...golly, I'm startin' to sound like Guy...Oh yeah, please post reasonable size images. Check this out in that regard
http://www.irfanview.com/
Once downloaded and installed, simply select file, then open your file, select image then resize, select the 640 x 480 pixels or any other size desired (hopefully smaller), click okay, then go to file and select save. I generally choose the 640 x 480 pixels option. If you want to keep your outrageously large image, be sure to copy it or rename your resized pic so that it doesn't overwrite your obscenely huge photo. Your time and attention is appreciated. Elmore

 

[Sylvatica]

Fallgirl, are you in a USDA hardiness zone 4 region? I would think that is pushing the limit for Acer palmatum 'Viridis' and 'Dissectum'. Your problems could be caused by that alone, or along with a few cultural issues. A split may be the result of freezing. But it also may be the delayed consequence of drought, root injury (concealed), flush pruning cuts, a handling bruise to the stem, even planting too deeply.

Dig a few 8" deep test pits outside of the rootball. Is it wet, dry, compacted...?