Tag cedar elm

For many of us, mistletoe is a welcome feature of the Christmas holidays; a decorative sprig hung in hopes of stealing a kiss. In nature, however, mistletoe is a parasite that can infest many different plant species, leeching water and nutrients, and can be not only unsightly, but hazardous to the health of a tree.

What is Mistletoe?

Mistletoe is the common name for several different species of plants in the order Santalales. In North Texas, and over most of North America, the most-commonly seen species are in the genus Phoradendron, such as Phoradendron tormentosa, or Christmas mistletoe. Several different species of tree can serve as host to mistletoe, including oaks, pecans, and hackberries, but in North Texas, mistletoe is most commonly found in cedar elms. Mistletoe is easily identified by its small, leathery green leaves and white berries. During the fall and winter, when the host tree’s leaves have fallen, mistletoe identification is even easier, as its leaves remain green.

Mistletoe is a hemiparasitic plant, which means that it gets some, but not all, of its nutrients from the host plant. Its leaves allow mistletoe to produce some food internally, but the plant cannot grow by itself. The seeds are most often spread in bird droppings or by other animal contact. The mistetoe’s berries, which contain the seeds, are attractive to many species of bird, but mistletoe berries are toxic to humans and pets.

Is Mistletoe Bad for Trees?

As a parasite, mistletoe does have an adverse effect on its host plant. Mistletoe takes water and nutrients from the host tree’s sap, which can deprive the branches of food. While a low to moderate mistletoe population may have no noticeable impact on the host tree’s health, as infestations grow, interruption to the tree’s nutrient cycle can lead to a loss of vigor. Trees with underlying stressors, such as drought, can be more easily affected by mistletoe.

Can Mistletoe be Removed or Prevented?

Unfortunately, there is no universally effective chemical treatment for mistletoe. Removing affected branches remains the only proven way of managing a mistletoe infestation. Mistletoe develops a root structure in the tree’s sapwood, which means the host branch must be completely removed to prevent regrowth. For larger infestations, however, it may not be practical to remove entire affected limbs. In these cases, removing the surface mistletoe growths can help slow its spread, but will need to be repeated. Whichever method of physical management is used, mistletoe removed before it begins producing berries (that is, during the first three years of its life) can be more easily controlled. Once the mistletoe has fruited, it can spread quickly through bird activity.

At Texas Tree Surgeons, we love trees and we love our community! While we are always happy to see mistletoe at the holidays, we want to keep our North Texas trees free from its effects. During the fall and winter, after leaf drop, is not only the best time to trim your tree, but is the ideal time to remove mistletoe, when its bright green leaves stand out against the gray and brown branches. Think your tree has mistletoe and want some management options? Give us a call, and one of our ISA Certified Arborists will be happy to take a look!

Another installment in our series of posts where Texas Tree Surgeons answers your tree questions. Are you having problems with your trees and want to know what’s wrong? Let us know!

My cedar tree has bagworms. Can you treat for that?

Bagworms are a common pest in North Texas, especially on cedars, junipers, cypresses, and other evergreens, although they can attack broad-leaf trees (like oaks, maples, and elms) as well. While they are common, they may not always be noticeable, especially on evergreens, as they use material from the trees they infest to camouflage their casings. Like other insects, bagworms have a year-long life cycle, and control measures depend on the growth stage of the pest.

What Are Bagworms?

• Bagworm is the common name for several different species of insect which are actually a type of moth (order Lepidoptera, family Psychidae).
• The bagworm caterpillars are very small (about 1/25 of an inch long), and spin silk thread which they use to attach themselves to plants and to weave into their bags.
  • Unlike a typical cocoon, the bagworm’s casing functions as a moveable shelter, with the caterpillars exiting to find food and climb up the plant.
• Once the caterpillar has matured, it undergoes a metamorphosis period before emerging as an adult.
  • Male bagworms resemble small moths while the females are flightless.
• Male bagworm moths seek out females during mating season, and the female uses her bag to lay eggs.
  • The exact times of caterpillar and adult emergence varies from species to species and is dependent upon the weather.

Can You Treat For Bagworms?

While bagworms are not prevalent every year, once they have infested a tree, they will continue to live there unless controlled.

• The simplest control method is to remove the bags.
  • They can be pulled off by hand or sprayed off with high-powered water.
  • It it important to dispose of the bags or destroy them, and not just leave them lying on the ground, as the eggs they contain can hatch and re-infest the tree.
• Insecticide sprays can be used to control bagworms, but are most effective when the caterpillars are small, and can be completely ineffective if the bagworms close their bags, as they do to molt or over the winter.
  • Systemic insecticides may be used in some cases as a preventative measure. Consult a certified arborist to see if this may be a good option for you.

At Texas Tree Surgeons, we love trees and we love our customers! Bagworms are a widespread nuisance and, while one or two may not harm a mature tree, can cause large-scale defoliation if left unchecked. It is a good idea to remove any bags that you see, whenever you see them. If you have bagworms, and want to see if there might be a chemical treatment option, contact us to set up a visit from a certified arborist. We offer full-service plant health care, including fertilization to help trees stressed by bagworms recover. We look forward to hearing from you!

After a devastating weather event like the tornadoes on October 20, 2019, the damage can be hard to assess, let alone start to repair. While damage to homes and other structures is of utmost importance to the community, addressing the damage to our urban forest, and determining what can be saved, is a key component of recovering after destruction.

Cleaning up downed trees is the first priority in an emergency situation. Fallen trees can prevent first responders and repair crews from accessing damaged utility lines and dangerous structures. Once the trees on the ground have been addressed, however, we must think about those left standing. After a high-wind event like a tornado, the trees left standing often have severe limb breakage and defoliation, or loss of leaves. Both of these issues have short- and long-term consequences, that must be understood.

Tree Safety Is Key

As soon as possible after a storm, owners of damaged trees should take a few steps to ensure there is no further damage to people or property:

• Clear the area around any damaged trees of vehicles and valuables and take steps to prevent access to the area.
  • If possible, cordon off the entire dripline area (from the trunk to the tips of the branches).
  • If there is a tree that could fall on your home, consider staying out of that part of the house until the tree can be assessed.
• Once the area has been secured, contact a certified arborist to assess the damage to your trees.
  • The International Society of Arboriculture (ISA) has established the Tree Risk Assessment Qualification (TRAQ) to train certified arborists in the proper evaluation of the safety and stability of trees. Be sure to find an arborist who has completed the TRAQ program.
  • Ask the arborist about tree stabilization, such as bolting and cabling. These measures can help prevent future issues with splitting trees.
• Trees that are stable, but have lost a great amount of the canopy will probably need fertilization or other plant health care measures to recover.

Will My Trees Survive Tornado Damage?

Ultimately, the prognosis for a storm-damaged tree depends on several factors, including the species, location, soil condition, and underlying health of the tree. Based on our experience, however, certain North Texas trees should fare better than others.

• Live Oaks, Cedar Elms, Pecans, Bur Oaks – Uncertain/Wait and See

  • While these species are resilient, we are assessing them on a case-by-case basis.
  • If the tree is stable, we recommend waiting until the spring to see if new growth appears.

• Red Oaks, Maples – High Risk for Sun Damage

  • Both types of trees are susceptible to sunburn, which dries out the bark, causing it to peel off,  and exposing the sapwood underneath to damage.
  • Even if the tree is stable, the risk of stress and dieback from the winter sun is great.
  • Maples and red oaks that have lost their leaves have little protection from sun exposure.

• Crape Myrtles – High Chance of Survival

  • As long as the crape myrtles remained in the ground, they should survive.
  • Damage to limbs and safety pruning may alter the shape of the tree, but should not cause any major issues.
  • If increased insect activity is observed, consider using insecticidal soap in the winter or pesticides in the spring.

• Mulberries – Uncertain/Wait and See

  • Mulberries are fairly hardy, and may survive, but may suffer from dangerous instability.
  • Once tree is stabilized, wait to reassess during the next growing season.

• Hackberries – Uncertain

  • Have the root area examined by a certified arborist for signs of root rot or kretzschmaria.
  • Even if the tree appears undamaged, the hackberry’s tendency to develop root instability issues may make it a fall risk in the future.

• Magnolias – Unlikely to Survive

  • Extensive defoliation will likely stress the tree past the point of survival, and prevent recovery from any damage.
    • As evergreens, magnolias depend on their leaves year-round.

• Ornamentals – Likely to Survive/May Want to Replace

  • Smaller trees and ornamentals seem to fare better in high winds, as they are able to flex with the pressure.
    • One risk to smaller trees is being damaged by falling debris from larger trees or structures. If there is no physical damage, the tree is probably stable.
  • Many smaller ornamentals are understory trees, used to shade from larger species.
    • As with red oaks, risk of subsequent damage from sun exposure is high.
  • Even if the tree survives, it may not be as well-suited for its space after the damage, and owners may prefer to replace it.
    • Defoliation or wind damage may have irreparably altered the shape.

What Should I Do Now?

Whatever kind of tree you have, and however it has been damaged, contact a certified arborist to determine the best steps to take. We highly recommend fertilization for all trees impacted by storms, especially in our urban soils. If your trees are going to recover, they will need all the nutrients they can get. If your landscaping has been disturbed by the tornado, now might be a good time to adjust your mulching practices to help enrich the soil going forward. If you need guidance, we are always here to help.

At Texas Tree Surgeons, we love trees and we love our customers. We are shocked and saddened to see the widespread damage and devastation after the recent tornadoes, and our hearts go out to all those who have lost their homes. So much of our beautiful urban forest seems to have been uprooted or destroyed, and we want to do what we can to preserve what remains. We hope this overview has been helpful, and we are always available to come out to assess your specific trees for damage, stability issues, health issues, or to give you our recommendations for post-storm care. Don’t hesitate to contact us with any questions you may have.