While driving around northern Utah this week it was easy to see among the most commonly planted street trees are the lindens. Their stately upright, oval shape and their attractive heart-shaped leaves earned them a place as a great tree for Utah.
These are not what most people are noticing right now. Their most commented on feature for several weeks near the end of June is their intoxicating fragrance. The fragrance comes from small flowers that are sometimes barely noticed but can never be ignored.
Asking someone to describe it is futile. Published descriptions place it as "citrusy" and offer a myriad of other descriptions. The scent is so strong that it is often noticed from several hundred feet away.
It is sometimes used as a perfume base and to flavor various herbal teas and other drinks. The blossoms themselves are so distinctive that beekeepers prize the very pale but richly flavored honey that comes from the nectar of these trees' blossoms.
There are some 30 species of lindens that are native to much of the temperate Northern Hemisphere. They are generally very cold hardy and do well even in high mountain valleys.
While they are known as linden trees in Utah, the same trees are called lime trees in Europe. They are not related to the citrus lime but the name comes from an old English or German word meaning flexible.
While no one in Utah grows this tree for lumber it is highly prized because it is soft and easily worked. It has very little grain so it is excellent for carving, model building, musical instruments and other uses.
By far the most common species planted in our area is Tilia chordata or little leaf linden. The term "Chordata" describes the heart shaped leaves. This European native has naturalized in the U.S. It has strong conical habit and grows 60 or 70 feet tall.
The American linden or Tilia americana has larger leaves and is commonly known as basswood. This large shade tree has a more spreading habit. The most common cultivar is "Redmond" which has more reddish branches in the winter.
Tilia tomentosa is known as silver linden and is sometimes sold locally. It seems to be more tolerant of alkaline soils. It has attractive foliage that has a dark green surface with a silver-white underside. It is not as cold hardy as other species.
Tilia x euchlora or Crimean linden is a hybrid with a loose, more graceful habit. It is somewhat tolerant of urban conditions, though it does not tolerate intense sun, heat, and drought.
Almost all lindens grow well to their natural shape with a minimum of pruning although grafted cultivars sometimes sucker badly. Most of them also develop a rich, golden color in the fall.
While I have extolled many of the virtues of these trees, no tree is perfect. Probably the most common complaint is aphids that attack the plants in the spring.
Aphids are attracted by the sugary tree sap. They produce excess syrup or honeydew that drops onto sidewalks, patios and vehicles underneath which makes a sticky mess. The sugary exudate also attracts ants, bees and wasps.
Most years, patience is the answer because the predatory lady beetles, green lacewings and other insects control and clean up the aphids. Spraying the aphids is counterproductive because it usually kills these predators and makes it necessary to spray for the pest for the rest of the season.
Cottony maple scale also attacks lindens. It looks like small quarter inch cottony masses on the twigs and branches. Spray with a dormant oil or insecticidal soap when the trees are dormant.
Sometimes the leaves are limp and distorted. The trees are not very tolerant of dry soil nor do they like to be over-watered. They are also very susceptible to broadleaf weed killers. Avoid applying them around the trees.
Another complaint from those who don't appreciate the trees is that they drop stuff. Trees that produce flowers also drop those flowers that may need to be cleaned up. Later, they drop the ribbon-like, greenish-yellow bract which has the pea-like seeds attached. Of course, like all deciduous trees they also drop leaves in the fall.
Get acquainted with these trees. They have many great qualities and they just might find a place in your landscape.
Larry A. Sagers is a horticulture specialist for the Utah State University Extension Service at Thanksgiving Point.
RED BUTTE GARDEN CLASS:
Easy Tree Identification, June 25, 6:30-7:30 p.m. JayDee Gunnell, USU extension agent, will introduce 25 desirable specimens and easy tree identification techniques. Contact Jessica Buxton at 801-468-3187 or at [email protected] The class will be in the Red Butte Garden Classroom, is free and the public is welcome.
WASATCH COMMUNITY GARDENS WORKSHOPS:
Chickens, Ducks, Turkey, and Fowl Workshop, June 27, 6-8 p.m. at the Grateful Tomato Garden at 800 S. 600 East. This is an in-garden workshop on how to keep and care for backyard fowl. Registration is required. There is a $10 fee, but scholarships are available.
Seventh Annual Downtown Tour de Coops, June 30, 10a.m.-2 p.m. A self-guided tour of backyard chicken coops north of 3300 South. Register online to receive the tour booklet.