Hi, my name is Rebecca... I'm new to maples! lol Last August I bought two japanese maples blood goods on sale at the local Loblaws/Superstore. I realize probably not the ideal place to buy, but for 9$ a tree, there was a deal - and the trees themselves appeared in good condition. I bought each tree from a different store, so each might be from a different greenhouse/grower in origin. Now the details! I'm located in Barrie, Ontario. Both trees were in one gallon buckets, I planted them in large 3' wide holes in which I put some fish meal, some clean triple mix and peat to encourage root growth before the winter hit. I did mean to cover them for the winter, but never got around to it (probably the 9$ tree factor made it not so urgent! - we just moved into our house a year ago and had a lot going on). They were buried in their holes no deeper than where the soil in the pots met the trees originally. Both got gnawed on by deer (just buds at tops), which is amazing because one tree (north side of house) is no less than 5 feet from the house... and we live in a quiet older subdivision. Due to the harsh winter, both trees appear to have died back to approximately 1' from the ground (to where the depth of the snow likely protected them). Tree1: Healthy... winter die-back aside. Planted on north side of house, gets mostly late afternoon/evening sun as it's shaded by the house. Healthy growth about half foot from base - good healthy leaves, the rest of the tree above all buds appear dead, but branches are flexible and healthy colour. Tree2: The one with the weird growth. This is planted on the south side of the house, fairly open area, with a big brother healthy clump of silver birch providing primary shade. The die-back from the winter is the same as Tree2 - all the upper branch buds appear to have died, but the stems appear to still be flexible and the majority thus far are a healthy red in colour. It too has gone to healthy leaf in areas within about a half foot from the ground, and then everything else above is dead/dormant. However, I just noticed the main stem/trunk has a discolouration about half way up (above the healthy leaf growth area) at first I thought rabbits had got to it and killed it because it's light brown in colour and similar in texture to particle board (looked chewed at first). Until I noticed the discolouration was actually slightly raised and spreading up the trunk. (I'm attaching pictures). I can't seem to google anything that matches this textured growth on the stem... so I thought I'd try and pick some brains instead. All I ever see written about is the wilt issue, which this clearly is not... Any and all help appreciated - I'm also wondering if I should prune back the maples to the growth area, or hope that the healthy stems might rebud later in the season? Thanks! Becca
The whiteish looking area is undoubtedly dead. Not sure exactly what pathogen causes this colouration but have seen it before in branches that have died back over winter. May even be a secondary infection that gets into branches damaged/killed by the cold. On a practical note prune back to just above where the healthy limbs emerge from the trunk, and also take out any dead twigs below this point. As you mentioned, the snow cover protected the lower parts from cold damage. The trees were new arrivals from the nursery and may have had very soft growth that was not fully winter hardy. Hopefully they will get acclimatised to your conditions and fare better next winter. One caveat: I am not sure exactly how cold your winters are there, but if it is colder than USDA zone 5 they may die back to the snow line every year.
