Learn from the arboriculture expert: Ernest H Rezents.
Interview by Hannah Lutgen, CTAHR extension agent Maui
I recently had the pleasure to interview Ernest Rezents, a renowned arborist in Maui County and author of Maui County Planting Plan. Let’s meet Ernest and learn about arboriculture in Hawaii. This interview was lightly edited for content.
Hello, thanks for meeting with me. Please tell us a little bit about yourself.
I was born and reared in Maui. I attended St. Anthony’s school for 12 years and The University of Hawaiʻi at Mānoa (UH Mānoa) for 5 years where I studied education. I taught math and science at Honoka‘a and Waipahu High School. I went back to the UH Mānoa and took physics and biology. Then I taught technical physics, trade science and electricity to train people to become journeyman electricians at Maui Technology School. Then I studied botany UH Mānoa. I returned to Maui and taught botany, physics, trade science part time, and electricity at night for the apprenticeship program at the Maui Community College (MCC). I went to Stanford University and studied physics and science education for a summer-this was an eye-opening experience. I returned to Maui to teach botany and physics at MCC. Towards the end of my MCC career, there was a need for landscape training. I obtained state funds to build a greenhouse and a classroom building furnished with microscopes, etc. and start a horticulture program. Joeseph Souki, a member of the Hawaii House of Representatives, helped finance this project. A greenhouse was installed, and I taught the horticulture program full time. I went to University of Oregon to get a Master’s Degree in biological sciences and enjoyed this tremendously. I also studied arboriculture at University of California Davis. Afterwards, I returned to Maui and taught arboriculture to prepare individuals to take the exam to become a certified arborist.
How long have you been working as an arborist?
I have been a certified arborist for 26 years now. In 1995 I became a certified arborist. After 5 years as an arborist, I attended a workshop sponsored by American Society of Consulting Arborists (ASCA) which gave me the credentials to be a registered consulting arborist. In that preparation I studied legal and became an expert in tree evaluation, report writing and expert witnessing pertaining to tree issues.
What do you enjoy about arboriculture?
I am amazed how such a big specimen can grow from a seed. Trees provide us with fruit, flowers, shade, and numerous environmental benefits. Research has indicated that hospital patients that have a view of trees from their room have a quicker recovery time compared to patients without a view of trees. Also, research suggests that people will travel further, stay longer and spend more money if there are shade trees in the parking lot where they park to shop.
What are the biggest challenges in the arboriculture industry?
Topping trees. When the tree crown is removed you lose all the benefits of the crown such as shade, oxygen, fruit, and wind protection. People top trees to make it short because they are too big and treacherous. People should prune trees annually but do not remove more than 25% at one time. This pruning needs to be done by an ISA certified arborist that adheres to arboricultural principles.
What is the arboriculture industry currently doing well?
More and more certified arborists are being hired. People are recognizing that such training is important. Certified arborists should have liability insurance, know how to make proper cuts, and be equipped to climb trees without spikes such as using ropes and/or a boom.
The Maui County Planting Plan (MCPP) contains a wealth of information. Will you please briefly explain what Maui County Planting plan is and how landscape architects and arborists across that state of Hawaii can utilize this information?
The Maui County Planting Plan is a guide that can help anyone select a tree to fit their environment and needs, and learn how to plant, stake, prune, water and maintain plants. This plan contains specific information and characteristics about a variety of trees, groundcovers and turf grass listed by scientific and common name. There are no invasive species in this guide and people can use this guide to find helpful information about installing parking lot trees, planting and pruning trees with illustrated pictures.
To me, the island planting zones are key. Robert Hobdy (an exceptional botanist) developed these planting zones based on rainfall and temperature for Maui County. If you live on a different island, refer to the map and tables and extrapolate to find your zone to determine which plants are suitable for your location.
What are your favorite street trees, shade trees and trees for parks, greenways, or open spaces?
For street trees, I love shower trees (Cassia sp.) they are beautiful and not too big. Monkeypod trees (Samanea saman) are big and provide great shade, but they can be expensive to prune. Nevertheless, monkeypods provide numerous benefits, they can increase property value, provide shade in parking lots, and create a welcoming approach for shoppers and homeowners.
Will you please provide advice for coconut palm tree pruning and explain the figures?
In the past, coconuts were pruned from 10 to 2 (bolohead) meaning that everything below the 10 o’clock and 2 o’clock position on the tree was removed. Now, as in the figure 2 above, people remove the lower fronds so that the tips of the upper fronds fall from 9 o’clock to 3 o’clock, which is preferred for the benefits in the crown. The leaves are food factories for the tree, allowing the tree to draw water and produce carbohydrates from carbon dioxide leading to trunk expansion.
When you over prune a coconut, it can cause an hourglass like, narrow section in the trunk due to a lack of vascular tissue, the water and food conducting tissue needed for normal expansion. After the tree grows and produces adequate fronds the coconut trunk will return to the normal trunk diameter.
Monocots, such as palm trees, have a terminal cambium situated on the growing tip.
Once monocots reach a certain size and growth the trunk expansion ceases. In comparison, woody dicots expand throughout their lifetime because the cambium is situated below the bark and phloem and above the xylem so the whole trunk may continue to expand.
What are your thoughts regarding spiked and spike less climbing?
In my opinion, using spikes to climb trees causes injuries on trees, which may affect the capillary function of the xylem and create a wound where fungi and bacteria can enter. Instead of using spikes on broadleaf trees, use ropes or equipment with bucket trucks. Spike less pruning on palm trees is commendable. The use of a climbing platform or a bucket truck, if there is adequate space available, are great options to prevent tree injury. Once you wound a palm tree, that wound will never heal, it will always be visible. Tourists have asked me, why are these palm trees full of holes? I tell them it’s because of spiked climbing. Puka, puka, puka.
What advice do you have for new or learning arborists?
Study and follow the International Society of Arboriculture (ISA) guidelines and become a certified arborist to do good work and maintain health of canopy and the tree. Trees are essential mankind and society.
Will you please briefly explain this figure?
Before pruning this tree, assess tree and remove branches that are decayed, rubbing or extremely long. Thinning extremely long branches on a mother branch creates space for light penetration, increases air flow and decrease weight load because excessively long branches may snap off. The tree in the good picture represents a well-maintained canopy with adequate branches and leaves. The tree in the bad picture is defoliated and will struggle because leaves that create energy and food for the tree are absent. The tree benefits are in the canopy.
Typically branches originate at the growing tip of the tree, and therefore as the trunk expands it engulfs or grows around this branch to provide good attachment to the tree. If you top a tree frequently you will have a lot of branching occurring from the cambium just beneath the bark opposed to the cambium in the trunk or growing tip so these branches will be attached weakly to the trunk and more susceptible to drop or break.
Thanks for your time Ernest!
For more information, please read:
Maui County Planting Plan,
MCPP 2015 Third Edition (mauicounty.gov)