We’re experimenting with plant cloning at our Warwick nursery.
What is cloning?
The term “clone” is from the Greek word klon, meaning a slip or twig. Plant cloning is the scientific process that uses cells from a plant to reproduce one or multiple genetically identical specimens.
What plant species are being cloned?
At the moment, Jack’s poplar is the only species being cloned. This tree is a hybrid species between the balsam poplar and an eastern cottonwood. Jack’s poplar is not common in the Credit River watershed. One of the only locations they’re found growing is in Mississauga, growing along the shingle bar at Rattray Marsh Conservation Area.
Why are plants being cloned?
The emerald ash borer (EAB) has killed hundreds of ash trees at Rattray Marsh. As a result, many areas in the marsh are bare and lack forest cover. Cloning may be a way to help the forest community recover more quickly and cost-effectively.
Jack’s poplars may not naturally grow new seedlings for many years. The trees may drop seeds but conditions may not be favorable for the seeds to root. If a seed takes, it may not be exposed to enough sunlight and it may grow slower than usual. Growing clones in a controlled environment drastically increases tree survival and can allow for a more cost effective recovery of some areas of Rattray Marsh Conservation Area.
In 2010, CVC staff cloned and then planted about 15 Jack’s poplars on the shingle bar at Rattray Marsh. Half survived.
How are plants being cloned?
Leading the cloning experiment is Bryana McLaughlin, an invasive species technician at CVC. Last February, she went to Rattray Marsh Conservation Area and cut small branches (only a few inches long and about the thickness of an index finger) from four different Jack’s poplar trees. These trees are known as “parent” trees.
The cut branches were then bound into bundles and put into moist soil for the rest of the winter. The moist soil allows the branches to develop callus, the undifferentiated tissue that eventually become the future roots (similar to stem cells in humans).
In May, the developed branches were placed individually in the aquatic bed at our Warwick nursery. An aquatic bed is similar to a soil garden, except the roots of the plant are submerged in water.
Bryana experimented with growing the branches using different methods. Some branches were planted together in a large pot and others were planted individually. This was to see if the branches grew faster and stronger in one environment over another.
The clones that survive the summer of 2017 in the aquatic bed will be potted and carefully watched so they can be planted in a conservation area the following year. The Jack’s poplar previously planted in the shingle bar at Rattray Marsh will continue to be monitored to see how they are taking to their new environment.
Cloning is an inexpensive and interesting way to lend Mother Nature a helping hand. Bryanna and other CVC staff will continue to experiment with cloning Jack’s poplar and possibly other plant species in the future.