Budding Interest

Winter is a good time to look at some of the finer details of trees and shrubs — their buds, for example. Buds!? Bo-o-o-oring, you say? Not really, if you take the time to appreciate details such as their shapes, colors, and textures.

Plum buds about to pop

Buds can do more than just help you wile away winter hours. They can disclose a plant’s identity as well as foretell for you what what’s in the offing for the upcoming growing season as far as flowers and fruits.

A bud contains the beginnings of a shoot or a flower, partially developed and telescoped down into a compact package. Except for adventitious buds, more common in some plants than others, that appear haphazardly along stems or trunks, buds appear along stems at distinct locations, called nodes. A node is where a leaf was attached last summer, and this winter’s buds were formed in the crotch where leaves and stems joined. 

In some plants, including fragrant sumac and black locust, the node is apparent from the leaf scar even though the bud itself, buried within the stem, is not visible now.

Opposite or Alternate (Nothing Political)

Noting the arrangement of buds along a stem is the first step to identifying a leafless tree or shrub in winter. Buds on some plants arise directly opposite each other. On other plant, buds are “alternate,” that is, arising singly on alternating sides of the stem.

Peach, pawpaw, willow, viburnum, cornelian cherry

Because buds can grow out into stems, you will find that opposite or alternate bud arrangement mirrored in a plant’s stem arrangement. Not always, though, because not all buds awaken into stems come spring; some remain dormant and others open to become flowers. And then there are stems that die and fall off. And plants having adventitious buds can have stems pop up just about anywhere.

It turns out that most deciduous trees have alternate buds. So if you happen upon a leafless tree in winter that has, instead, opposite buds, you can pretty much bank on its being an ash, horsechestnut, maple, or dogwood tree. Of course, once you identify a tree as, for example, a maple, you have to look for other details, such as the bark or fallen leaves, to tell if it is a red, sugar, silver, or Norway maple.

An acronym can help you remember those opposite-budded arboreal outliers: MADCapHorse. Maple. Ash. Dogwood. Caprifoliaceae (the honeysuckle family, which incudes elderberry, viburnums, and, of course, honeysuckle). And Horsechestnut. Those Caprifoliaceae are shrubs and shrubs generally have opposite buds, but it makes for a more euphonious acronym.

Here in the Northeast, I’d just as soon remember the four plants, ash, horsechestnut, maple, and dogwood.

A problem with MADCapHorse is that the list of apposite-budded trees can be puffed up further if nonnative trees, such as katsura, paper mulberry, olive, African tuliptree, and paulownia, are in the running. 

Or, back to a native: catalpa, which has whorled buds, that is three buds all originating from the same apex. (I just cut a stem from my catalpa tree and it looks like the three buds are slightly staggered rather that arising in the same place.)

Budding Beauty or, at Least, Interest

Whatever. Now take a closer look at the buds themselves of some trees and shrubs. They vary in color, size, shape, and texture. Witness the elongated mahogany buds of pussy willow and the brown velour buds of pawpaw. See how some plants — viburnums, for example — have naked buds, enveloped only by the first pair of leaves. Buds of most plants are protected by a scaly covering.

Pawpaw buds

Notice also that mature plants have two kinds of buds. Come spring, those that are longer and thinner will expand into shoots. Flower buds are usually fatter and rounder. Look at how dogwood flower buds stand proud of the stems like buttons atop stalks.

Flower buds of cornelian cherry, a dogwood relative

And take a look at a peach branch with some compound bud: a single, slim stem bud in escort between two fat flower buds.

Peach buds

Apple and crabapple flower buds occur mostly at the ends of stubby stems that elongate only a half an inch or so yearly.

Apple spurs with short fat, fruit buds

Rhododendron flower bud and shoot buds

Predict the Future

Because many plants lay down the beginnings for the coming year’s flowers during the previous year, looking at buds is a useful way to predict now what kind of flower show or fruit crop to expect as warm weather rolls in. If the show looks like it’s going to be paltry, you may have to lay blame on the weather or something you did this past growing season.

Buds of trees and shrubs will soon begin to swell ever so slightly in anticipation of spring, but their actual growth is held in check until they experience enough long days and/or chilly (32 to 45°F) weather. Once daylength and chill requirements are fulfilled, plants recognize that winter is over and await warmth to begin growing.

The amount of light and cold needed before warmth can prod growth varies with the kind of plant. Native plants generally know what they are doing, awakening after danger of cold injury is past. Nonnatives may not be so wise, so their impatient blossoms or new shoots frequently succumb to cold. 

Apricot or almond are good examples of nonnative plants whose upcoming crop is frequently snuffed out when overly eager flowers are snuffed out by frost. Problem is the they have too short a chilling requirement for some climates (mine, for instance).

Apricot orchard n bloom

Blossom damage need not influence survival and growth of the plant itself.

Once buds have chilled long enough and are ready to grow, you can hurry them along with artificial warmth — indoors. Snip off some stems of dogwood, peach, apple, or forsythia and plop their butt ends into vases of water. For a good show, make sure that the stems you cut have plenty of fat flower buds.

(The above information only scratches the surface of buds and twigs. Some excellent resources, such as Fruit Key and Twig Key to Trees and Shrubs by William M. Harlow and Key to Missouri Trees in Winter, let you delve deeper, systematically leading you along in the identification of a slew of trees and shrubs.)