Saturday, December 13, 2008

It's Alive!

Every year for a long stretch now, we've gotten a live tree for Yule.  

Live trees are trickier than the cut ones for lots of reasons.  One of them is dormancy.  Even evergreens are dormant in winter.  The difference they have from their deciduous cousins is that they retain their leaves.  In order to do this they employ a number of tricks--coated leaves, more compact leaves with an overall greater thickness than most deciduous leaves (to help resist frostbite) and specialized sap.  This doesn't make them invulnerable to cold, though.  They don't put on new leaves, which isn't tough enough to resist the cold, all winter long.  They just maintain.

Contrary to appearance, they do shed their leaves like all other trees.  They just do it like we shed hair.  Sometimes they'll have precipitous loss from stress, but they usually let go of leaves only when those leaves are too old to do a good job.  No pension plan for those leaves, I'm afraid.  After they're shed, many varieties of evergreen leaf also serve as a chemical mulch that makes the soil inhospitable to most seeds.

Anyway, opinions vary on how long it takes for a tree to break dormancy, but opinions are universal that it's a bad thing.  The tree will lose an entire flush of growth that was meant for spring.  So it loses an inch or two of ground at the start of the year, you think.  No big deal, right?  But it's not just height it's losing.  Remember, it loses its leaves fairly continuously.  If it loses its entire spring flush of buds, its going to have to spend extra energy to try to recover.  It needs to produce more leaf mass to make up for what it lost to frost in addition to what it naturally loses, plus it still needs to add on a little more length on its limbs (they prioritize height because it helps them claim valuable solar space and helps choke out competing weeds.)  The tree can also go into shock.  Since transplant shock is pretty well a given for trees anyway when you plant them in your garden, the additional shock of breaking out of dormancy, getting tossed outside back into cold weather and losing all its new buds, and then having to come up with extra growth just when its energy reserves are at their lowest--you can lose the tree entirely.  As in it may die.

So although having a live tree is really, really neat, we have to plan around it.  First of all, we try not to keep it in the house more than ten days.  Second, it can't be downstairs where the woodstove is running continuously.  In addition to that heat being very drying, it's so extreme that it may break the tree out of dormancy even sooner.  Last, we have to be careful about the lights (as low heat as we can find and keeping them on only when we're actively enjoying the ambience,) ornaments (not heavy or hung in a way that will damage branches) and how often we water (can't just 'top it off' like a cut tree--having it be too wet is just as bad as too dry.)

The fuss is worth it.  When I stroll through the garden, I recognize all our Yule trees from years past.  Some of them have grown a lot, like our variegated cedar, while others, like our variegated holly, are still compact (and are supposed to be that way.)

BTW, this is a Moonglow juniper, in honor of my DH, who loves junipers.  The link leads to a reasonable description, but there's an error--these trees can mature up to a height of 30 feet and can be wider (up to 12') so planning for 15'x5' is asking for trouble unless your climate naturally dwarfs them.  Planting in rocky soil will also probably dwarf them, though junipers aren't as stymied by rock as some other trees.

All this started with some good friends of ours (hi Sondra and Rick!) who gave us a miniature Christmas tree one year to plant in our yard.  It's still tiny, but easily three times as big as when we got it.  It's a dwarf alberta spruce, and you can usually find them very inexpensively at most stores this time of year in a variety of sizes.  Even people with very, very small gardens can plant this tree outside.  They grow only a fraction of an inch each year, and maintain a tidy shape without pruning.  Treat them more like a shrub than a tree.  By the time they get 'tree-sized' your grandchildren will be enjoying having their grandchildren over to decorate the outdoor Christmas tree.

Have a happy holiday!

1 comment:

Things that puzzle this other goddess.... said...

LOL I had almost forgotten that tree! I couldn't help giving it to you, I have a black thumb and you are ever so much more eco conscious than I!

I've never been able to get Rick to do anything but a fresh cut tree. Being the extremely practical scrooge I am, I could probably deal with a fakey looking artificial tree for all that I notice the tree every year. Much rather would enjoy them outside where I can smell the fresh air with them. :D