Q: I had someone cut some tree branches that were too low, but I’m not sure how to check if he did a good job. What am I looking for?
A: Trees develop their own version of scarring after pruning cuts are made, which closes the wounds to form a barrier to wood decay and invasion by wood insects. The formation of this protective layer is hindered when pruning cuts are made too close to the trunk, and the risk of infection of the trunk by fungi that cause cancer increases if it is left too long of a branch stub . Since there is little we can do to intervene after a poor cut is made (do not apply a wound sealant or other types of “paint” or tar), it is critical to make pruning cuts in the correct place.
The base of a branch meets the trunk in a region called the branch neck. The neck is the tissue of the trunk, not the tissue of the branch, which is an important distinction since the tissue of the trunk should not be damaged in the pruning of branches. The top of the junction of the branch and the trunk is called the branch-bark ridge, and it can look like a miniature mountain range of bark pushed-up into a slight ridge that runs along each side of the base of the branch Together, these specialized areas form a ring wrapped around the base of a branch, and contain the tissues that will close the wound.
Branch pruning needs to remove only enough of the branch’s wood so that the callus tissue from the neck region can close over the short stub of exposed wood, but it does not need to remove all of the trunk wood. same making a cut more flush with the trunk. tea”appropriate pruning cuts” section of our page “Pruning Trees” contains an illustration of where to cut, and more details can be found in the booklet of the USDA Forest Service. How to prune trees. Iowa State University Extension has a great video showing technical pruning on a young tree as an example of what to look for, as the same principles apply to older trees and larger branches. (On his YouTube channel, the video is titled “Pruning Principles – Making a Good Cut”).
If you see a “donut” ring of callus tissue that forms throughout the pruning cut about a year from now, that suggests that the cuts made were done well. Depending on the circumference of the branch removed, the complete closure of the wound could take several years, which is normal. Always have both a certified arborist the gold has Licensed tree expert in Maryland Do a pruning job when you are not sure where to cut or unable to handle larger, heavier or taller branches.
Q: How can I tell if my orchid is growing a flower tip or another root?
A: Although the shapes and sizes of the roots and flower spikes will depend on the type of orchid, there is still a fairly easy way to tell them apart. On “moth orchid” phalaenopsis, the most cultivated type of orchid, the spikes emerge between the leaf axils (where the leaves join the stem), as do the roots. For others, such as “dancing ladies” orncidiumthe roots emerge low on the base of the foliage as a bulb, called a pseudobulb, and the spicules emerge between the leaves above.
Orchid roots are covered with an absorbent layer of cells called velamen, which helps protect the roots from damage, keeping moisture and nutrients in soilless environments (such as the top of the tree), where most orchids live. On the living roots, the velamen will be either white (possibly stained by a potting mix at the time) or silver. The root tip, if actively growing, will be vibrant green or even rosy. In contrast, a spike will be a green color even throughout its length, and its tip will generally be more blunt in shape compared to the taper of a root tip. The direction of growth is less distinct; usually, the roots grow down or out, and spikes upwards, but this can vary depending on how the plant is grown, the direction of the light source and the type of orchid.
The shortest days of winter is a common flowering season for a variety of orchids (a reason exhibitions and sales often take place at this time of the year), because you can see a small nub emerging from a phalaenopsis stem around now and wonder if it is a spike or root, take a look at its shape: if mitten-like, with one or more clefts in the end, it is a spike; if it is smooth and uniform, it is a root. When it grows, a spike will also develop at least one node (joint) in the stem, a bit like the band that surrounds the body of an earthworm. When the flowers on a spike fade, sometimes one or more of those nodes will be able to produce a second flush of flowers before the spike dies.
The University of Maryland Extension Home and Garden Information Center offers free gardening and pest information at extension.umd.edu/hgic. Click “Ask Extension” to send questions and pictures.
