Thursday, November 29, 2012

Conifers Revisted

The grounds at Welkinweir are pretty far from green at the moment.  Ice on the pond and naked trees will be the view for a few months yet.  It is the time of year to be extra thankful for anything green.

The Pinetum at Welkinweir should be the top winter destination for any visitors.  The earliest spring blooming plants are nearby, and the wall of various conifers is a reminder of livelier seasons.  Zooming in on the wall can be a delightful experience.

First, we have the three most common types of conifers in North America: pine, fir, and spruce.  They are all in the same family (Pinaceae) but have key differences.  Pine needles prefer to practice the buddy system.  In other words, they stick together on the branch in groups (more formally known as fascicles) of two to five.  Spruce and fir do not share these sentiments; their needles are borne singly along the branch.  To know which one is which, you could foolishly grip the branch and see if it inflicts pain (spruce) or not (fir), but there is a less painful test.  Fir needles are generally flat with blunt tips.  Spruce needles are sharp on the ends, and they will roll easily between your fingers, and they radiate outward from the branch evenly spaced and almost forming a perfect circle.  Test your Christmas tree!

Pinaceae family

Dragon's eye pine

Japanese umbrella pine

White pine

Deodar cedar

Don't let this plant trick you.  It is in the pine family, but not one of the big three mentioned above.  The sharp, singly attached needles might make you think it is a spruce, but notice the needles are not uniformly distributed around the branch.  The needles aren't flat, so it isn't a fir.  Cedars often have whorls of needles on very short side branches.  By the way, I love this plant.

The needles on this Colorado blue spruce are very sharp tipped, and radiate in an almost perfect circle around the branch.  If you were to pull one off the plant, it would roll between your fingers.

Two things make this plant obviously a fir. One, if you touch the needles you will find they are flat with blunt tips.  Two, notice that most of the needles protrude sideways and upward, with very little on the underside of the branch.  Now compare that to the spruce photo above.

Tsuga canadensis 'Slenderella'

Don't let hemlock trick you.  It doesn't follow the needle rules of pines, but it is in the same family as pine.  An amateur might be tempted to classify this as a very odd looking fir or yew.

You think this is a fir? Good guess, but no.  Hemlock? Nope!  This is yew, and taxonomists are still trying to decide how to classify it.  Let's just say that it is in the Taxaceae family for now.  You can differentiate from a fir because of the very broad needles that seem directly attached to the stem, whereas fir needles have a sort of suction cup at the base of the needle.  Yew can easily be identified by their red seeds that resemble berries. Not berries you want to eat though!  This plant comes with a toxic punch.

Cupressaceae family

There are other families of conifers besides Pinaceae.  Instead of needles, they have scale- (lay flat against the stem, like fish scales) or awl-like (short, wedge-shaped and pointy) leaves.  Juniper, arborvitae, cypress (cryptomeria, cupress), and false cypress (chamaecyparis) have these characteristics.  Other than juniper, I have great difficulty distinguishing between these conifers.

Variegated juniper

Junipers have scale- AND awl-like leaves.  The new growth is awl-like and prickly to the touch.  Another easy way to identify junipers is the presence of bluish berries.

'Gold Rider' Leyland cypress 

Cryptomeria (also, confusingly, called cedars)
These have awl-like leaves and are easily my favorite.  Check out the variety of cryptomeria we have in our Pinetum at Welkinweir!

'Elegans Nana'




'Oregon Blue' Lawson falsecypress

Chamaecyparis pisifera 'Boulevard'

Come visit Welkinweir!

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