Posts Tagged ‘trees in the united states’

Tree Spotlight: Northern Catalpa

Catalpa is a tree you may not have heard of, but once you see one you won’t forget it. With showy spring flowers, bean-like pods, and bearing one of the largest leaves of any tree in the northern hemisphere, it is a beautiful sight. Let’s join the Arbor Day Foundation in shining the spotlight on one of the most unique Michigan trees.

And if you want to see a truly magnificent one, the Michigan State Record lives on the lawn of the Capitol in Lansing.

Northern Catalpa: Rarely Unnoticed

By James R. Fazio | November 7, 2017

catalpa-flowers-iStock-597270638-1080x608

Catalpa speciosa

Catalpa is a hard tree to overlook. Trumpet-shaped flowers herald its awakening for the summer and are soon followed by some of the largest leaves in the northern hemisphere. Elephant ears would not be too far off the mark for their description. Finally come the seed pods — bean-like in shape draping the tree like green tinsel.

There are two key species of catalpa in the United States — southern and northern catalpa. Originally, southern catalpa was more widespread, but when the pioneers discovered the northern species in a very limited area of the Midwest, it didn’t take long to realize that this one grew larger and could tolerate colder winters better. Thanks to its fast growth and rot-resistant wood — and a promotional campaign by Nebraska governor Robert W. Furnas, a contemporary of J. Sterling Morton — farmers began planting it for fence posts and to sell as railroad ties. Today, as a shade tree, it is widely distributed in parks and yards throughout the country.

Catalpa is not a tidy tree. Maintenance people complain about cleaning up after it when the flower petals, leaves, and seed pods drop. But that may be a small price to pay for this tree’s tolerance to a wide range of growing conditions, its dense shade, and the interest it adds to the landscape. Guy Sternberg, author of Native Trees for North American Landscapes, has said that the old trees of this species, “become rustic and picturesque, their weathered crowns testifying to the passage of previous wind storms, and would look very much at home towering over Boot Hill on Halloween.”

Whether young and vigorous or old and stagnated, catalpa is a tree in the landscape that is difficult not to notice and enjoy.

What’s in a Name?

The common names for catalpa are many and colorful. Some of these include Johnny smoker tree, Linden log tree, cigar tree, stogie tree, bean tree, western catalpa, hardy catalpa, Catawba, caterpillar tree, and fish-bait tree.

The scientific name makes less sense. The genus is the same as the common name, Catalpa, and comes from the name that Cherokee Indians used for this tree, Catawba. The species name, speciosa, is from the Latin for — not surprisingly — species. The “osa” part is from osus, or “full of,” said to be in reference to its showy flowers.

In the Landscape

The catalpa tree is a tree that demands your attention. White, showy flowers, giant heart-shaped leaves and dangling bean-like seed pods make is a great ornamental tree. It reaches up to 60 feet in urban settings and grows well in a wide range of soils (hardiness zones 4-8).

While not ideal for every location, this unique and hardy tree is a fast grower that finds a home in parks and yards throughout the country.

Where Are The Trees?

If you ever wondered where the trees in the U.S. were, wonder no longer. The Woods Hole Research Center, U.S. Forest Service, and U.S. Geological Survey have created a visual inventory in the form of the map below. Using data from several different sources, they have determined the density of forests across the country; the darkest areas have the tallest, densest, most robust forests growth.

Where the Trees Are: Image of the Day

Where the Trees Are

Color bar for Where the Trees Are
download large image (4 MB, JPEG, 4457×2809)
acquired January 1, 1999 – December 31, 2002

 

Trees are one of Earth’s largest banks for storing the carbon that gets emitted by natural processes and human activities. Forests cover about 30 percent of the planet’s surface, and as much as 45 percent of the carbon stored on land is tied up in forests.

But did global forests hold more or less carbon in the past? And could they store more in the future? Does it matter where those trees are growing? Scientists really don’t know. But before they can find out, they’ll need a reliable inventory of what is growing today.

Josef Kellndorfer and Wayne Walker of the Woods Hole Research Center (WHRC) recently worked with colleagues at the U.S. Forest Service and U.S. Geological Survey to create such an inventory for the United States. The map above was built from the National Biomass and Carbon Dataset (NBCD), released in 2011. It depicts the concentration of biomass—a measure of the amount of organic carbon—stored in the trunks, limbs, and leaves of trees. The darkest greens reveal the areas with the densest, tallest, and most robust forest growth.

Over six years, researchers assembled the national forest map from space-based radar, satellite sensors, computer models, and a massive amount of ground-based data. It is possibly the highest resolution and most detailed view of forest structure and carbon storage ever assembled for any country.

Forests in the U.S. were mapped down to a scale of 30 meters, or roughly 10 computer display pixels for every hectare of land (4 pixels per acre). They divided the country into 66 mapping zones and ended up mapping 265 million segments of the American land surface. Kellndorfer estimates that their mapping database includes measurements of about five million trees.

“Forests are a key element for human activity,” says Kellndorfer. “Resource managers need to see forests down to the disturbance resolution—the scale at which parking lots or developments or farms are carved out by deforestation. We have to know how much we have, and where, in order to conduct sound management and harvesting.”

Learn more about the creation of Kellndorfer’s map and other attempts to measure Earth’s forests in our newest feature story: Seeing Forests for the Trees and the Carbon: 
Mapping the World’s Forests in Three Dimensions.

NASA Earth Observatory map by Robert Simmon, based on multiple data sets compiled and analyzed by the Woods Hole Research Center. Data inputs include the Shuttle Radar Topography Mission, the National Land Cover Database (based on Landsat) and the Forest Inventory and Analysis of the U.S. Forest Service. Caption by Michael Carlowicz.

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