Fall doesn’t officially begin until later in September, but everyone considers Labor Day the unofficial start. Typically, the nighttime temperatures begin to fall while the daytime temperatures stay warm. It’s also when the rains return so new plantings will receive sufficient water without your having to supplement it with irrigation. And, that’s exactly why the nursery industry reminds us that Fall is for Planting.
Garden centers join in on this promotion, too. Contrary to some people’s opinion that garden centers just use the fall season to get rid of leftover nursery stock, reputable garden centers actually get fresh stock for the season. They may mark down stock that’s left from spring sales, also. That’s OK because most of their nursery stock will be perfectly fine, if they took care of it. So, how do you tell a good tree from a bad one? The International Society of Arboriculture (ISA) published a consumer information bulletin, Buying High-Quality Trees, in which they offered the tips below.
A high-quality tree has….
• Strong form with well-spaced, firmly attached branches.
• A trunk free of wounds or damage.
• A quality root system to support healthy growth.
Conversely, a low-quality tree has…
• Weak form in which multiple stems originate from the same point and branches grow into each other.
• A trunk with wounds from handling or incorrect pruning.
• Limited, crushed or circling roots in an undersized root ball or container.
Some of the ways you know a tree’s form is strong is even spacing of branches along the trunk. Avoid branches facing upward and forming narrow angles. As the branches grow, they’ll compete with the trunk for the limited space between them and branches usually lose the fight and break. Trees in which the trunk splits into two equal leaders can be a problem as it grows. Those two leaders are called co-dominate but one is always stronger. If the angle between them is narrow, the weaker will inevitably split. This can be prevented by cabling and bracing but that’s an extra expense. It should be noted that the limbs you see on a young tree will seldom survive to maturity, but the spacing will remain true to form. Branches don’t grow upward; they remain in the same position for life. As the trunk grows higher, it shoots out new branches, while the lower ones are shaded out by the upper branches or have to be pruned off for clearance purposes.
Always inspect the trunk of a tree you’re considering buying. Look for signs of insects, wounds like frost cracks (injuries to the bark that run vertically up the tree), and improper pruning cuts. Sometimes the grower removes the lower branches to encourage a fuller crown. If flush cuts – those flat to the trunk – were made, special tissue in the branch collar was removed. This tissue contains cells that help the pruning wound to callous over to protect the tree from insect or diseases. Any pruning cuts should bulge out like a donut but shouldn’t leave any branch stubs. If the trunk is wrapped in protective material, remove it and inspect the trunk before you buy the tree.
Whether the tree is bare root, balled and burlapped or containerized, you should check the roots before buying. Bare roots are easiest to check. Make sure the roots are moist and not discolored or crushed. The roots were probably pruned when the tree was dug. Make sure the root ends are cleanly cut, rather than ragged as though they were ripped from the ground. If the roots are long, the ragged end can be pruned so it’ll grow correctly. Containerized plants are the next easiest to check at the garden store before buying. Slip it out of the pot and look for roots encircling several other roots. If present, try pulling the offending root out straight. If it’s too big to be straightened, pass on the tree, unless the garden center offers to fix it for you at no charge. The repair involves cutting the offending root and removing the section that crosses other roots. A girdling root that remains in place can eventually kill all or part of the tree. Also check the root collar, the point at which the root and trunk connect, to be sure it’s not buried in the container soil. If it is, pull the soil away and make sure that collar remains exposed when you plant the tree.
Balled and burlap roots are the most difficult to check. However, you can check the root collar and make sure it isn’t buried. Be sure to retain the right to return the tree if you find any root damage like girdling root when you get the tree home. You’ll cut the string or wire holding the burlap to the trunk when you plant the tree, and that’s when you can examine the rootball closely.
Regardless of whether you buy a bare root, containerized or balled and burlapped tree you should keep the roots moist but not sopping wet if you aren’t going to plant it right away. When you do plant it, dig the hole two or three time larger around than the rootball but only as deep. Before planting, remove the pot from containerized trees but just the string or wire from balled and burlapped trees. The burlap will decompose in the ground. Spread the roots out when planting bare root stock. As you backfill, stop periodically to tamp down the soil lightly but not enough to compact it. Be careful not to bury the root collar. Finally, water the backfill.
Most trees prefer to be planted while young and small. Small trees will get established faster and grow bigger sooner than bigger trees of the same type. Eucalyptus and oak are particularly sensitive to confinement, and can take several years to recover before they start to grow. Birches, although quite resilient to confinement are slow to get started as big trees. For example, #5 (5 gallon) trees grow faster and bigger than #15 (15 gallon) or boxed trees that get planted at the same time. Crape myrtle, palms and trees with fibrous roots are the most resilient, and can be planted at any size. It is important to know which trees can be planed as large specimens before investing in large specimens.