Thursday, April 16, 2009

The Birth of Trees

The old saying from tiny acorns, mighty oak trees grow is a good one. Trees, some of our largest living organisms, begin life from seeds. Powell Gardens does propagate some of its trees from seed. If we want to protect and display a particular population of plants, this is often the only way to do so. Why protect a particular population? We know that the wild trees from a specific area often have traits that make them more adapted to a particular region. It is well documented that many trees with widespread ranges (say Eastern North America), those from the more southern part of the range may not be winter hardy in the northern part of their range and those from northern parts languish in the heat when planted in the southern part of their range. Trees from drier regions of their range are often more drought tolerant is another example. Sometimes certain populations have more disease resistance too.

Here is a tray of young Butternut (Juglans cinerea) trees that have germinated from butternuts collected from underneath a wild tree not far from here. Butternut is a tree in trouble -- an imported canker disease has wiped it out from much of its range. Where I grew up I have watched all the mature trees die, a few saplings still grow but all are infested with the canker. Before long, they will be gone as remaining trees never live long enough to produce nuts (their seed). Powell Gardens is just past the butternut's native range, so trees planted here do not yet get canker disease.

Here is a closer look of young butternut trees. Seeing the luxuriant growth of these young seedlings inspired me to write this blog. I hope one day they will grow and produce the tasty, football shaped nuts beneath their uniquely flat-topped crowns. Their beautiful silvery plated, charcoal striped trunks protect a most beautiful light colored wood -- too rare to be of commercial importance.

Marie Frye (Senior Gardener -- Plant Records & Collections) is in charge of growing all our unique trees. Here she takes a closer look at her baby butternuts as today they will be transplanted into individual deep, open bottom pots so that they can grow strong roots that will be naturally "air pruned" as their roots reach the bottom of their new container. This is a good way to grow plants that have deep tap roots as seedlings.


Marie planted many Shagbark Hickory (Carya ovata) nuts too. See my Old Hickory blog for part of their story. These are grown in competition for a national program sponsored by a local garden club. Shagbark Hickories grow roots and not crowns for the beginning of their life so are not available at local nurseries (they are not cheap to produce and take time). They are very ornamental and important trees and these will be planted at various locations around the metro so their kind will not be lost.


Here are seedlings of Cucumber Magnolia (Magnolia acuminata). Cucumber Magnolia is a large shade tree native on the west side of the Appalachians from Ontario to Alabama and makes a fine shade tree here but is rarely if ever available at nurseries. These are grown from seed of the magnificent tree near the Southwest corner of Loose Park.



Sometimes we do propagate trees from cuttings to ensure an exact clone of a plant. This is a cutting grown young Southern Magnolia (Magnolia grandiflora). Because we are at the northernmost place where they will successfully grow outdoors, we have propagated some of the region's best examples to find a more hardy one for local gardens.


It hard to believe that this tiny seedling is from the largest tree in our region! This is a seedling of a Baldcypress (Taxodium distichum) grown from a massive, 8 foot diameter trunked tree near Mayview. Eric Tschanz (Powell Gardens Director) and I stopped in to visit its owner and collect seed on the way back from a meeting in Columbia. Obviously this tree has the genes to be a survivor in our region. Someday I would like to propagate all of Greater Kansas City's champion trees for planting at Powell Gardens.


These are seedlings of wild Flowering Dogwoods (Cornus florida) grown from trees on the western edge of their range not far from here. We hope they are better able to survive the vagaries of our weather as Flowering Dogwood can be fickle here -- if planted from too far south it is not hardy or if from too far east it doesn't like our lower humidity and rainfall.



This is a Dwarf Hackberry (Celtis tenuifolia) seedling from a local wild tree. Dwarf Hackberry is not the most ornamental of trees but is very heat and drought tolerant, hosts 5 species of butterflies' caterpillars, produces sweet berries for us and birds, and grows only 15 to 18 ft. tall at maturity.



Speaking of edible plants, these are seedlings of some of our select Pawpaws (Asimina triloba) now growing in the yet to open Heartland Harvest Garden. Maybe one day they will produce the best tasting pawpaws ever! A good way to find new varieties is to plant out seedlings and test them over time.


This seedling has traveled around the world. It is a Pistachio (Pistachia vera) grown from the hardiest known Pistachios in Uzbekistan. We purchased it from One Green World which is a great nursery that introduces hardy edible plants from around the world. This is one of 3 seedlings -- Pistachios are male and female plants and you can't tell the boys from the girls until they start to bloom. These seedlings will be planted in the Fun Food Garden section of the Heartland Harvest Garden.



The tall spindly tree in this picture is of a very special plant started from a special population of trees. It is an Oklahoma Live Oak (Quercus fusiformis) donated by Steve Bierberich,owner of Sunshine Nursery in Clinton, OK. It is grown from a relic, disjunct Oklahoma population of the Escarpment Live Oak (the same live oaks you see in Austin, Texas). It has proven to have good hardiness into the lower Midwest! Our two trees will be planted in the Vineyard portion of the Heartland Harvest Garden where they will add to the Mediterranean theme of that garden. The acorns of this species are very low tanin and were once an important human food source.

May this blog inspire you to plant trees, from seed or from your favorite nursery: just get out and plant them! As 2004 Nobel Peace Prize winner, Wangari Maathai, who started The Green Belt Movement to plant trees and restore the environment and democracy in Kenya, said in her acceptance speech "to give back to the children a world of wonder and beauty." Wangari Maathai also has a Greater Kansas City connection as she received her bachelor's degree in biology from what is now Benedictine College in Atchison, KS.
All photographs were taken in Powell Gardens' greenhouses on April 15, 2009.

1 comment:

Jeff said...

I found this entire blog to be informative and interesting. I learned much and am inspired to grow some trees native to middle Tennessee from seed...thank you!