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The Monday Garden
Shades of Maple: Identification by Bud

Issue No. 157 - March 27, 2005
by Sue Sweeney

Most tree buds are wonderful tiny sculptures, joys of winter and very early spring that are too often left unappreciated. Maple tree buds are no exception. To add to The Monday Garden series on our wonderful native maples and not-so-wonderful invasive ones, this issue covers the buds.

It’s not hard to distinguish sugar (Acer saccharum), box elder (Acer negundo), Norway (Acer platanoides), and sycamore (Acer pseudoplatanus) maples by the buds alone. You also can able tell that a tree is a maple and definitely a red (Acer rubrum) or a silver (Acer saccharinum), but telling a red from a silver by the buds alone is a tricky business, beyond the scope of this article (and usually my ken).

picture: early waking insect embraces the terminal bud of a young silver maple, Mill River at Scalzi Park March 2005.
Ash or maple? To get started, North American trees with opposite branching are most likely to be ashes or maples. You can rule out the ashes by looking for a flat-topped, thick bud with a pronounced triangular shape; look also for a diamond pattern to the bark in mature trees.
pictures: buds and barks of various ashes; note the fat, thick, triangle top of the twig and the diamond shaped patterns of the bark. Stamford, CT, March 2005 respectively: the Mill River at Scalzi Park, the Tully Center, and Cove Island.
Cross-breeeding: Remember that cross breeding is the rule among trees of the same family. While cross-breeding might be good for tree health, it does make identification difficult. (Is Homeland Security aware of tree stealth?) As a general matter, for maples at least, it’s best to confirm a tentative ID using at least three aspects of the tree such as bark, form, buds, leaves, etc. Even then, be only 90% certain until you’ve watched the tree go through its annual cycle and compared it to several others of the same species. Go to Issue 134 (October 16, 2004) for an overview of these other features. There are also separate articles on The Monday Garden site on most of the maple trees.

Sugar maples: The sugars have buds that remind some observers of upside-down sugar cones (or at least it’s a good mnemonic). To me, the precise, overlapping bud scales look like the spires of an art deco building. The terminal buds often come in groups of three, arranged like a trident. Compared to other maples, the sugar buds are smaller and finer cut, with sharp points. Caution: other maples’ buds can resemble sugars when the buds first peek out. I find this especially true of silvers and reds but then the tree’s bark or form may help confirm ID. If the bark has that very curvy look that only sugars (sometimes) can have, or if the tree has the low, multiple-trunk crotch with upward curving branches that only sugars (sometimes) have, then you can be pretty sure that you have a sugar. If neither of these tell-tales are present, you may need to wait until the buds mature before confirming the identification.

pictures: sugar maple buds, Stamford CT,Winter 2004-2005, respectively, the First Presbyterian Church, and Strawberry Hill.
Conversely, when you’re being confused by sugar, red and/or Norway maple leaves with “cross-over” characteristics, you may be able to sort the trees out by the buds.

Second caution: some sugar maple buds are almost dead ringers for red oak buds, so make sure you’ve checked for opposite branching and are checking the bark.

Red maples: Many of the reds go from tiny sugar-maple like bud points to big (about half pea-size) red Christmas ball buds so early that you can use the buds as an ID point almost year round. However, the buds of some reds don’t mature until fall or winter. Whatever, by early spring, most reds will have eye-popping deep red ball clusters. The reds also tend to have very silvery-gray bark that’s smooth on young trees but rough, or even shaggy, on older ones.

picture: the characteristic bud clusters of a red maple on light gray twigs. First Presbyterian Church, Stamford CT March 2005.
Silver maples: The silver maples tend to swell their buds much later than the reds but then bloom first in the spring. So, it’s often hard to tell by the buds alone if you have a red that’s not fully swelled its buds or a silver. The very first tree to bloom in my area, though, is the silver. It can beat the crocus and is a major boon to early-waking pollen and nectar eaters. Some times, the bark is not just rough but shredded and pealing with an orange undercoat or the trunk on a very old tree has become very silver and has developed amazing lumps. Very young silver saplings tend to have bright orange twigs and very red bud scales. If any of these conditions are present, you probably have silver. However, silvers and reds are very closely related and you may need to wait until you see the flowers, leaves, or seeds (“samaras”) to be certain.
pictures: silver maples, bud to flower. Stamford, CT March 2005. Scalzi Park and Strawberry Hill. twigs.
pictures: silver maple trunks, Stamford CT March 2005 Chester Street and Cove Island
Box elder: The box elder (the ash-leafed maple – see Issue 138, November 14, 2004) may be considered a “trash tree” but the buds are beautiful: downy silver and rose on bright green to olive green shiny twigs. If you need confirmation, look at how the old bud scale scars between the side buds meet in the middle with a point.
pictures: Box elder buds, Cove Island, Stamford CT March 2005
Norway maples: The nastily invasive Norways have the biggest, fattest buds; dramatic in fact. The bud scales are deep mahogany often with lime green tinting. When the bud scales pop, some Norways have a gold hairy under-covering over the flowers-to-be. Again, the buds can start as tiny points like a sugar but look for the smooth, textured gray-brown bark.
pictures: Norway maples buds Stamford CT March 2005, Picture 1: Cove Island; Pictures 2-4 Strawberry Hill
Sycamore Maples: The invasive sycamore maples have green buds a bit smaller than the Norways’ but similarly shaped. The sycamore maple tree itself is a Norway-ish shape but the bark ages differently. It can stay very smooth or get squarish cracks and patches, almost like a fruit tree.
pictures: sycamore maple buds and trunk, Stamford CT March 2005, Grayrock and Forest Streets.
From The Monday Garden. Copyright © by Sue Sweeney. Reproduced with permission. 

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