Friday, January 6, 2017

A Disguise

The Colorado blue spruces that were planted on a raised berm at the back edge of our property have been in decline recently.

They were little green pyramid blobs when first installed in 2006. It was hard to picture them forming a line that would ever screen anything.

But they did. By the winter of 2012 they had grown majestically and were quite a sight -- five in a row, staggered a bit for visual interest, and screening the back of our house nicely.

I never thought they would turn the interesting blue that I had expected. They were green for the first years, but then began to develop the blue cast that Colorado blue spruces are known for. In fact, they became a real steely gray color.

But as soon as they had become stately, blue, dense and tall, they went into decline. Of the original five, two are gone now. We had to take two out in 2014 because of extensive branch dieback. They were looking very sparse and half dead.

Three remain, but the one on the end is looking bad now too. The lower branches are dying out from the inside. There are healthy blue needles only on the very tips of the branches. The inner part of each branch has died back.

It gives the tree an open, droopy, empty look at the bottom and it will get worse, probably until we have to take the whole thing out.

Spruces do not regenerate growth. The dead parts of the branches will not regrow. But Mike from Bartlett suggested helping the tree disguise its empty parts by stimulating more healthy growth at the tips. More needles at the growing ends of each branch will make it all look fuller.

How to do that? He suggested a root collar excavation. All of the spruces on the berm were planted too deep originally. It's a common condition when landscapers install trees, they simply put them in too deep. Additionally, the soft, newly dumped dirt of the berm settled over the years, and the trees kind of sank with the settling. Dirt piled up even more over the root flare, constricting nutrient flow and limiting growth over time.

That's not the main reason my Colorado spruces are in decline, though. They are a poor choice for our climate -- they want open, sunny, dry, cold places, like the Rocky Mountains they come from. Humid, warm, crowded conditions in my garden are not ideal, not even acceptable, as the declining blue spruces let me know.

But we'll do the root collar excavation in spring. Bartlett will use air spades to blast away the dirt compacted around the trunk without cutting any of the root mass away. They have done root collar excavations on a number of large trees on my property and the resulting growth stimulation is always impressive. It works.

So that will help my sad, sparse, blue spruce. New growth at the tips will be a clever disguise, at least for a few more years.

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