Dying street trees

A declining urban forest

It is that time of year when our urban forest seems to be lush, vibrant, and green.  Trees have finished leafing out, many have flowered and, with recent heavy rains, many are growing well.  To the casual observer, the urban forest looks like it is thriving.  People are planting trees all over town and nurseries are […]

The second flush of growth

We think of summer as the “growing season” and we are used to our garden plants growing all summer. For most trees, though, growth takes place mostly in the early spring. Most trees in temperate regions produce a single flush of growth – the bud opens, leaves that were formed the previous year expand to […]

flowering dogwood inflorescence

When is a flower not a flower?

Many trees are full of showy flowers at this time of year. A close look at these flowers can be quite rewarding. Flowering dogwood is one of our most popular flowering trees, but those beautiful white blossoms hide a secret. Take a close look at a dogwood tree and you will see that the showy […]

Street Lights and Tree Growth

Urban trees live with all kinds of stresses that their forest cousins do not – road salt, soil compaction, lawn mower strikes. They also live in a different light environment, one in which it is never completely dark.  Spend the night deep in the woods and the only light you will see is from the […]

Bur oak leaves

A Deep Green Autumn

A deep green autumn is rare in Kentucky. By this time of year, our trees usually look forlorn and bedraggled. Dry summers, high temperatures, insects and diseases all take their toll.  Not in 2015, though. Our frequent rainfall and cool temperatures have allowed many trees to maintain lush green leaves and to continue growing. Some […]

The Great Flush of 2015

Have you seen the Great Flush of 2015?  In Central Kentucky,  trees are growing very fast right now, producing new growth that is noticeable for its pale green or yellow colors.  Late flushes are complicated responses to changes in soil moisture. This is the first of several stories about the Great Flush of 2015, but […]

Showy flowers

Flowers, Pollen and Allergies

Is that tree causing your allergies?  That pretty tree with the white flowers?  That pine tree covering your car in green film?  Nope. It’s the trees you don’t see that are getting you. This is the height of allergy season. You can feel it in your sinuses and see it on your car windows. Huge […]

The Sap Is Rising

“The sap is rising” is an often heard description of early spring. If you cut into the stem or branch of certain trees – sugar maple, birch, hickory, walnut, or sycamore – on a cool spring day, you may see sap dripping from the cut end, or an icicle of sap forming.  The sap is slightly […]

Dead trees and what they can tell us

Dead trees are fascinating because they provide us with a permanent record of their lives. The annual rings that record the tree’s experience with drought, nutrients and temperature are familiar to most of us.  Somewhat less familiar, but easy to see, is the record of all the insults, accidents and stresses of life as a giant, […]

Keep Growing Until We Have to Quit – The Yellow-Poplar Strategy

Trees are generally very conservative in their growth habits. They often go to extremes to avoid rare events such as an early frost or severe drought. This is especially true of shoot growth. Although we think of trees as growing all summer, most trees only grow in height for a few weeks. Flowering dogwood sets […]

Mower damage, old (O) and new (N)

Street tree abuse – Part II

Street tree abuse is our term for management of street trees that results in their death, or in severe damage that shortens their lives. We have previously shown examples of this throughout the Lexington area. Now, we show an egregious example of street tree abuse while it is happening. The scene is the Legacy Trail, […]

Bur oak with lightning scar and lost crown

Lightning and Trees

Lightning and Trees seem to go together. Many fires in the Western US are started by lightning strikes on trees. Here in the Bluegrass and Nashville Basin, we find fire scars on a very large number of trees. Lightning rarely kills our trees, but it is an important factor in their lives. Lightning-struck trees lose […]

Leaves

What, if anything, is a species? Part 1

Two trees grow next to each other in a woods in the Bluegrass region of Central Kentucky.  Can you identify them?   Are these two different species or one?  Post your answers in the comments below or on Facebook, then tune in for a discussion of these pictures tomorrow.  Over the next couple of weeks, […]

Friday Tree

Friday Tree May Stump You

The Friday Tree for this week may stump some of you, but it is not really very hard. Give it a try in the comments below or on our Facebook Page. (click for a much larger picture)

Canopy shyness

Canopy shyness

Canopy shyness is the tendency of trees to reduce competition between adjacent trees by maintaining a space between branches. It is easy to see in tropical forest canopies. which tend to be flatter than temperate canopies. Looking up into a tropical forest canopy (in this case a lowland forest in Peninsular Malaysia), you can see […]

Second flush of growth

Tree are Popping

We think of summer as the “growing season” and we are used to our garden plants growing all summer. For most trees, though, growth takes place mostly in the early spring. Most trees in temperate regions produce a single flush of growth – the bud opens, and leaves that were formed the previous year expand […]

Friday Tree Followup

This week’s Friday Tree was tricky. Some of you got it, and some of you were very close. The two reasonable guesses were Catalpa, Catalpa speciosa, or desert-willow, Chilopsis linearis. The flowers of both these trees are similar, and they are closely related, but they occupy very different habitats: catalpa is a midwestern tree of […]

The best year to be a tree, Part 2

Part 1 described the unusual shoot growth pattern of trees this year.  Here we discuss why this happened. Everyone realizes that this was an usual summer in eastern North America.  We had a mild summer and a remarkable amount of precipitation.  This graph (click for full size) is from the NOAA Climate At A Glance […]

The best year to be a tree, Part 1

Now that the Autumnal Equinox has arrived, it is a good time to look back on this year in the Lives of Trees.   For Eastern North America, this has been a great year to be a tree.  Temperatures were mild to moderate for most of the growing season, soil moisture was adequate to above […]