An exemplar of the rare boojum trees that grew on campus for nearly 70 years was cut down March 12 because it was dying, but the tree is finding life as its tips are being cloned.
The tree was the oldest boojum in the United States and the tallest in Arizona, and was cut down because it had no chance of surviving, said Robert Perrill, a UA biomedical research specialist and owner of Boojum Unlimited who discovered the disease.
Perrill said he saw the upper stem of the tree was leafless and found rot completely through the base, confirming his suspicion the tree was sick. It is unclear what kind of disease the tree had.
The 37-foot Boojum was standing in the Joseph Wood Krutch desert garden on the UA Mall and had to be cut down almost immediately because it was likely to fall on the nearby sidewalk and harm people, Perrill said.
But even though the tree is no longer standing, it is not completely gone. A local horticulturist (who wished to remain anonymous) is attempting to root the healthy tips of the tree because, "It has historical value and it would be great to produce offspring from its genes to let it live on," Perrill said.
Perrill said once the tips have been rooted it can be called a clone because it has the same gene material as the original tree.
"We all have our fingers crossed," Perrill said. "We certainly hope to get at least one, maybe even two or three offspring."
The tips are dry but in good condition, even though they had no water for some time ranging from six months to three years, depending on when the disease started, Perrill said.
The root system and the top were separated from each other and the tree could not transport water and other nutrients that were needed for photosynthesis. But because the boojum is a desert plant, it is designed to survive arid conditions, Perrill said.
"Plants like this are slow to grow and slow to die," he said.
The UA laboratory of tree ring research received slices from the stem. Some wood was also donated to other universities in the United States to further research of the plant because boojum wood is not very common, Perrill said.
Mary Olsen, an extension specialist in plant pathology at the UA, is responsible for determining the boojum's cause of death by looking at tissue from the lower trunk and upper roots.
Olsen said she is unsure what the problem was but it might be bacteria or fungi that destroyed the tree from the inside.
"If we could find out what killed it, we would be able to protect other plants on campus," Olsen said.
The boojum tree was imported from Mexico about 70 years ago and by the time it was cut down, it was the oldest living plant that had been imported into the country, Perrill said.
There are four other boojums on UA property which are all significantly younger than the fallen tree.
Native boojum forests exist only in Baja California and an area in Sonora, Mexico. All other trees are imported or grown from a seedling, Perrill said.