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...... Pseudobulb Ragweed
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<br />Pruning cuts. After you understand how to
<br />approach a pruning job, you need to know how
<br />to make good pruning cuts. The first lesson:
<br />never leave a stub. Or to put it another way,
<br />always make a cut just above some sort of
<br />growth (a bud or a stem). To understand why
<br />this advice is given, think of a stem or branch as
<br />a conveying tube for water and plant nutrients.
<br />If you cut a branch some distance beyond its
<br />uppermost growing part, you leave nothing in
<br />the stub itself to maintain growth. The stub, no
<br />longer a part of the plant's active metabolism,
<br />withers and dies, although still attached to the
<br />plant. In time it will decay and drop off, leaving
<br />an open patch of dead tissue where it was
<br />attached. In contrast, when a cut is made just
<br />above a growing point, callus tissue begins to
<br />grow inward from the cut edges; in time, this
<br />tissue will cover the cut surface.
<br />There is a right way to make pruning cuts—
<br />and there are several wrong ways, as the illus-
<br />tration on the previous page shows. You want to
<br />avoid leaving stubs, and you also want to avoid
<br />undercutting the bud or branch. The best cuts
<br />place the lowest part of the cut directly opposite
<br />and slightly above the upper side of the bud or
<br />branch to which you are cutting back.
<br />Using pruning shears. When you cut with
<br />shears, be sure that the cuts are sharp: clean cuts
<br />callus over faster than cuts with ragged edges.
<br />Use shears that are strong enough for the job. If
<br />you can't get them to cut easily through a branch,
<br />the shears are too small, too dull, or both. Switch
<br />to a stronger pair of shears or use a pruning saw
<br />instead. With hook -and -blade pruning shears,
<br />remember to place the blade, not the hook,
<br />closer to the branch or stem that will remain on
<br />the plant. As illustrated on the next page, if the
<br />position of the shears is reversed, you will leave a
<br />small stub.
<br />Using pruning saws. Pruning saws come in
<br />handy when you need to cut limbs that are too
<br />thick for shears or loppers, or when a plant's
<br />growth won't allow your hand and the shears to
<br />get into position to make a good cut.
<br />Larger limbs—from wrist size upward—
<br />are heavy and need special care In removal. If
<br />you try to cut through one with a single cut, the
<br />branch is likely to fracture before you've
<br />finished the cut. The limb may fall, tearing wood
<br />and bark with it and leaving a large, ugly
<br />wound. To cut a larger limb safely, make it a
<br />three-step operation, as illustrated on the next
<br />page. The final cut should be made very care-
<br />fully. For years, the recommended approach
<br />was to cut the branch flush to the trunk. That
<br />has changed slightly. To avoid decay, make the
<br />final cut slightly outside the branch bark ridge
<br />(the compressed bark in the branch crotch)
<br />and branch collar (the natural circles or ridges
<br />where the branch meets the trunk), as shown in
<br />the illustration on the next page. If no collar is
<br />visible, the angle of the cut should match the
<br />angle formed by the branch bark ridge and the
<br />axis of the trunk.
<br />Pruning to shape. In shaping, your artistic
<br />side plays a role in determining what form a
<br />particular plant should take. Every plant has a
<br />natural shape; its growth tends to conform to
<br />a natural pattern, whether round, gumdrop -
<br />shaped, wide -spreading, vase -shaped, or arch-
<br />ing. Observe what a plant's natural shape is, and
<br />then prune the plant in a manner that will allow
<br />the natural form to continue to develop. Remove
<br />any excess growth that obscures the basic pat-
<br />tern or any errant growth that departs from the
<br />natural form. Use thinning cuts:
<br />When pruning to shape, make your cuts.
<br />above a bud or side branch that points in the'
<br />direction you'd like the new growth to take. If
<br />you have no preference, remember that gener-
<br />ally it is better for a new branch to grow toward
<br />an open space than toward another branch.
<br />Also, it is generally better for growth to be
<br />directed toward the outside of the plant than
<br />toward its interior. Try to eliminate branches
<br />that cross and touch one another. Crossing
<br />branches may rub together, suffering injury, and
<br />are usually unattractive, especially in deciduous
<br />plants out of leaf.
<br />Pruning for flower production. Flowering
<br />shrubs bloom either from new growth or from
<br />old wood, depending on the plant species.
<br />Before you prune, determine which sort of
<br />growth bears flowers. In this way, you can avoid
<br />inadvertently cutting out stems that would give
<br />you a flower display.
<br />Most spring -flowering shrubs bloom from
<br />wood formed during the previous year. Wait
<br />until these plants have finished flowering before
<br />pruning them (or do some pruning by cutting
<br />flowers while they are In bud or bloom).
<br />Growth that the shrubs make after flowering will
<br />provide blooms for the next year.
<br />Most summer -flowering shrubs bloom on
<br />growth from the spring of the same year. These
<br />are the shrubs you can prune during the winter
<br />dormant season without sacrificing the next
<br />crop of blooms.
<br />A few shrubs bloom twice or throughout
<br />the growing season (many roses, for example).
<br />Spring flowers grow from old wood; later
<br />blooms come both from recent growth and from
<br />wood of previous years. During the dormant sea-
<br />son, remove weak and unproductive stems and,
<br />if necessary, lightly head back remaining growth.
<br />During the growing season, prune as necessary
<br />to shape while you remove spent blossoms.
<br />Pruning conifers. These evergreens fall into
<br />two broad classes: those with branches radiat-
<br />ing out from the trunk in whorls and those that
<br />sprout branches in a random fashion. Spruce,
<br />fir, and most pines are examples of the whorl
<br />type; arborvitae, hemlock, juniper, and yew are
<br />examples of random -branching conifers. Prun-
<br />ing guidelines differ for the two groups.
<br />On whorl -branching types, buds appear at
<br />the tips of new growth, along the lengthening
<br />new growth, and at the bases of new growth.
<br />You can cut back the new growth "candles"
<br />about halfway to induce more branching, or you
<br />can cut them out entirely to force branching
<br />from buds at their bases. The point to remem-
<br />ber is that you must make cuts above potential
<br />growth buds or back to existing branches. Cut-
<br />ting back into an old stem—even one that still
<br />bears follage—won't force branching unless
<br />you're cutting back to latent buds.
<br />The random -branching conifers can be
<br />pruned selectively, headed back, even sheared;
<br />new growth will emerge from stems or branches
<br />below the cuts. But when you shorten a branch,
<br />don't cut into bare wood below green growth:
<br />most kinds (yew Is an exception) won't develop
<br />new growth from bare wood.
<br />Controlling beigbt. Some conifers—chiefly the
<br />random -branching kinds, plus deodar cedar
<br />and hemlock—can be kept at a controlled size,
<br />either as dense specimens or as hedges. When
<br />growth reaches within a foot or so of the size
<br />you desire, cut back all but about 1 inch of the
<br />new growth. This will produce enough small
<br />side branchlets to make full, dense foliage.
<br />Once this bushy growth forms at the ends of the
<br />branches, you can hold the plant to a small size
<br />year after year by shortening new growth that
<br />develops and cutting out any wild shoots.
<br />Repairing damaged trees When a conifer has
<br />been damaged by cold or breakage, you may
<br />have to remove entire limbs. It's almost impos-
<br />sible to restore the natural shape, but you can
<br />often make the most of the situation by trim-
<br />ming or training the damaged plant into an
<br />unusual sculptural form. If the central. leader
<br />has been damaged, you can stake one of the
<br />next lower branches vertically and train it as a
<br />new leader.
<br />Pseudobulb
<br />Adiickened, aboveground modified stem Is
<br />called a pseudobulb. Found In some orchids
<br />such as Cymbidium, it serves as a storage organ
<br />for nutrients.
<br />Purslane
<br />Purslane is a mat -forming annual weed. It
<br />thrives in damp or dry conditions and warm
<br />weather. Look for succulent, fleshy green -tared
<br />stems and dark green leaves, often tinged with
<br />red; pale yellow flowers open on sunny mornings
<br />(see photograph, p. 614). Spreading by seeds
<br />and stem fragments that root in damp soil, this
<br />weed is easy to dig out. Chemical controls
<br />Include glyphosate and appropriately labeled
<br />pre -emergence herbicides.
<br />Ragweed
<br />Ragweed, also called wild tansy or hogweed,
<br />is a particularly irritating weed because of
<br />the copious amounts of pollen It produces and
<br />the resulting hay fever it causes for millions of
<br />people in late summer and fall.. - . ;: ►
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