Betula Pendula "Youngii"

Between late July and the end of August 2010, the leaves dried up and dropped off of the birch. I checked for borers, but that isn't the problem. It was planted eight years ago , and has not prematurely dropped leaves before. Does anyone have an idea of what the problem is?

Sarah

You know, I have had the same problem with my three-year-old (planted) tree. The first year it dropped its leaves in August, I thought it was because it was newly planted a few weeks before and I hadn't given it enough water. Then, last year, it defoliated again although we had a record rainy summer. This year, with the drought (but copious supplemental watering) it again defoliated by August. So, what's up? I've noticed other trees in this area doing the same thing, but really hadn't noticed that before. Very strange. I see no sign of borer. In fact, I treat the tree with a systemic each spring, and thought that might be a problem. Every spring it leafs out beautifully and has doubled in size since planting, to about 11'.

John

Since the hardiness zone for this Birch is 3a to 6b do you think that it might be reacting to high summer heat?

i have this tree and have not had a problem - it is about three years in the ground and pretty large 8/9' - i think the first year it lost leaves earlier than others - maybe in the early oct time frame.

snapple45: The high heat was my first thought after it dropped leaves the second year. Guess we'll have to wait until we have a cool summer... whenever that might be! If not, I might have to offer the tree up to someone passing through one fall or spring!

Think foliar disease (like crabapples or buckeyes might have, which cause earlier defoliation - imitating scab or anthracnose) rather than insect damage. If you had borers tunneling around under the bark, you'd have whole sections of the tree dead, and likely dead leaves persisting on the tree.

I'm away from my references, and I don't grow birch so I can't address what the choices might be - but I bet that there are more than a couple. If sanitation isn't practiced, then the disease will be around seasonally.

VV: I haven't seen any signs of foliar disease on the leaves. Sometimes they don't even dry up first, but yellow and fall off. Birches can be picky, for sure, but I've seen this cultivar growing just fine in the area in previous years. I'll give mine a couple more years, then it'll be decision time!

The leaves looked good and healthy, then they turned yellow, then brown, and then began to drop off. the early fall. I had considered the heat and the many days of high humidity and high heat together this summer. Maybe that was the cause. This is a photo of it at night September 2, 2010. Most of the leaves are brown already.

quaintcharm: Aren't you in an area that experienced a drought starting in July this past summer? If so, and you didn't do any supplemental watering, that might be the cause of the problem. We had a terrible drought from late summer into November, and lots of shrubs and shallow-rooted trees, especially conifers, either defoliated and went into dormancy early, or died.

As an aside . . . why would anyone want to grow this hideously ugly, untidy tangled mophead-on-a-stick? It is the least attractive birch in the world!

Resin

resin how do you really feel:)

i like it.

Just as the appearance of most every Japanese Maple can be enhanced with careful pruning and training, I think any weeping tree, including 'Youngii' birch needs attention to help it form a beautiful branching structure. And it's true that too many people simply whack off the longer weeping branches as the tree gets larger resulting in a "mop head on a stick". IMHO, probably the most difficult weeping cultivar to make attractive is 'Snow Fountains' flowering cherry. In my area of the Midwest, it's rare to see an ugly weeping birch.

We had drought, but it was really humid, with little rain. We have a watering system on it, at the drip line. One of the reasons I likes it was because it looked like the dancing trees in the old cartoons from the 40's. We did lose a large limb in 2008, but the tree was ok in 2009. Thanks for your input, everyone.

quaintcharm: If you didn't supplement the drip line watering, it might very well have not been able to supply enough water to the tree this summer. When doing maintenance for clients this year, even those with irrigation systems had shrubs and trees that suffered from lack of water, and I had to really soak the landscaping (other than the grass) to get them through the drought. In my area, the drought was so severe that the soil was dry down to 2'.

Hopefully, your tree didn't suffer dieback, but just went dormant early, if the cause was not enough water, which I strongly suspect since it's never done this before for you. You'll know in the spring. Good luck!

From now on I will be monitoring it. I don't think it is dead. It looks like one secondary branch will have to be removed. I think you are right about the lack of water. There is a "Cully " River birch at the back of the lot. It is 20 years old, and 50 feet tall. It has been so carefree I think I expected the same from the Youngii . Thanks for the observations and advice, and I can definitely use the luck!

Not that any leaves dropping prematurely is a good thing, but it is a good sign that they turned yellow before dropping. Birches are notorious for yellow, dropped leaves when stressed. Even river birches in Minnesota will do it. Betula pendula and its cultivars (including 'Youngii') are far more susceptible to heat and related stresses.

Treat your tree (treat any plant, for that matter) holistically. Don't zero in on one environmental factor, but look at the whole. Irrigation is not necessarily the answer. Given that there is adequate water availability for birch, heat + high humidity is worse than heat + normal humidity. Evapotranspiration helps to cool the tree and evapotranspiration and evaporation helps to cool the soil. Both of these processes are greatly inhibited by high humidity. One might take into consideration that too much irrigation might be taking place, causing stress on the tree from overwatering, rather than underwatering, especially if the soil is clay based. What's good for the green grass isn't always best for the tree. A tree that is planted too deeply (not a good thing to begin with) will exacerbate conditions. If in doubt, always plant a tree more shallowly then more deeply.

Try installing a LARGE circle of mulch around the tree. Cool, moist, porous soil: that's what white birch love.

Rick

That is ALL good info and advice.