
Completely Arbortrary
Tree advocate Casey Clapp and his tree-curious friend Alex Crowson bring you a podcast about trees and other related topics. History, culture, art, religion, science... trees affect and are affected by everything. Join Casey and Alex on their silly and educational journey to prove it.
Latest episodes

May 8, 2025 • 1h
Fight Shrub (Butternut)
Put up your dukes, for a battle between the city, the people, and the trees. At the center is butternut (Juglans cinerea), and it's shading you, your neighbor, and your neighbor's neighbor. Then we play a new game with one rule... you do not talk about Fight Shrub.Completely Arbortrary is produced and hosted by Casey Clapp and Alex CrowsonSupport the pod and become a Treemium MemberFollow along on InstagramFind Arbortrary merch on our storeFind additional reading on our websiteCover art by Jillian BartholdMusic by Aves and The Mini-VandalsSee Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

May 1, 2025 • 57min
What a (Knobcone Pine)!
Who started the fire? It may have been the knobcone pine (Pinus attenuata) in a ditch attempt to RELEASE THE SEEDS! This curious pine has a curious way of dispersing which includes fire, cones, and cannibalism.Completely Arbortrary is produced and hosted by Casey Clapp and Alex Crowson Support the pod and become a Treemium MemberFollow along on InstagramFind Arbortrary merch on our storeFind additional reading on our website Cover art by Jillian BartholdMusic by Aves and The Mini-VandalsSee Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Apr 24, 2025 • 44min
Anomalous Secondary Growth (Ombú)
Anomalous secondary growth! What in the world is it? Just ask the ombú (Phytolacca dioica), pokeweed’s tree-like cousin. It doesn’t make wood, it makes “anomalous secondary growth”, an endlessly interesting way to grow. Then, we answer a question about the perfect flower/tree pairings.Completely Arbortrary is produced and hosted by Casey Clapp and Alex CrowsonSupport the pod and become a Treemium MemberFollow along on InstagramFind Arbortrary merch on our storeFind additional reading on our websiteCover art by Jillian BartholdMusic by Aves and The Mini-VandalsSee Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Apr 17, 2025 • 56min
Golden Cone Ratio (Austrian Black Pine)
The Golden Ratio: a fact of life on Earth, or an copy and pasted alien blueprint? Perhaps the answer lies in the cones of the Austrian black pine (Pinus nigra). Let’s discuss Phyllotaxis, the mathematical means by which plants remain in light.Completely Arbortrary is produced and hosted by Casey Clapp and Alex CrowsonSupport the pod and become a Treemium MemberFollow along on InstagramFind Arbortrary merch on our storeFind additional reading on our websiteCover art by Jillian BartholdMusic by Aves and The Mini-VandalsSee Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Apr 10, 2025 • 4h 10min
BONUS: Lord of the Tree Rings Marathon
What's up, Middle-Earthlings! Casey and I are taking a much-needed break this week, and so we present to you a hilariously massive extended edition episode that includes all three episodes of our Lord of the Tree Rings series, originally published in March of 2022. New episodes starting next week! Take care, everyone.Completely Arbortrary is produced and hosted by Casey Clapp and Alex CrowsonSupport the pod and become a Treemium MemberFollow along on InstagramFind Arbortrary merch on our storeFind additional reading on our websiteCover art by Jillian BartholdMusic by Aves and The Mini-VandalsSee Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Apr 3, 2025 • 1h
Inside Sprout: Joy (Money Tree)
What makes you happy? Is it money? Or maybe it’s the money tree (Pachira aquatica). This famous houseplant is also a forest tree, so why did it become synonymous with feng shui, harmonious qi, and interior design? Then we play a new game of Happy Go Lucky!Completely Arbortrary is produced and hosted by Casey Clapp and Alex CrowsonSupport the pod and become a Treemium MemberFollow along on InstagramFind Arbortrary merch on our storeFind additional reading on our websiteCover art by Jillian BartholdMusic by Aves and The Mini-VandalsSee Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Mar 27, 2025 • 1h 17min
Inside Sprout: Sadness (Weeping Cherry)
What makes trees weep? Perhaps the answer lies in the aptly named weeping cherry (Prunus x subhirtella 'Pendula'). Today we talk gravitropism and why some plants just have it backward. Then, we listen to you tree-themed Beatles covers and announce the winner of THE HAT!Completely Arbortrary is produced and hosted by Casey Clapp and Alex CrowsonSupport the pod and become a Treemium MemberFollow along on InstagramFind Arbortrary merch on our storeFind additional reading on our websiteCover art by Jillian BartholdMusic by Aves and The Mini-VandalsSee Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Mar 20, 2025 • 1h 11min
Inside Sprout: Anger (Jeffrey Pine)
What makes you angry? Is it the Jeffrey pine (𝘗𝘪𝘯𝘶𝘴 𝘫𝘦𝘧𝘧𝘳𝘦𝘺𝘪)? Perhaps it’s the smell, a controversial topic among tree lovers that causes all sorts of anger.Completely Arbortrary is produced and hosted by Casey Clapp and Alex CrowsonSupport the pod and become a Treemium MemberFollow along on InstagramFind Arbortrary merch on our storeFind additional reading on our websiteCover art by Jillian BartholdMusic by Aves and The Mini-VandalsSee Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Mar 13, 2025 • 1h 4min
Inside Sprout: Fear (Silver Maple)
Why are we so afraid of the silver maple (Acer saccharinum)? Perhaps because of the risk involved. In today’s episode of Inside Sprout, we discuss tree risk assessment as we ask ourselves the question: if a tree falls, and no one is around to see it, is there any risk?Completely Arbortrary is produced and hosted by Casey Clapp and Alex CrowsonSupport the pod and become a Treemium MemberFollow along on InstagramFind Arbortrary merch on our storeFind additional reading on our websiteCover art by Jillian BartholdMusic by Aves and The Mini-VandalsSee Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Mar 6, 2025 • 51min
Inside Sprout: Disgust (Black Locust)
Welcome to Inside Sprout, a 5 part mini-series on trees that best embody and illicit our most basic human emotions. Today we start with disgust and the black locust (Robinia pseudoacacia). This tree is almost universally despised for its invasiveness, but has found a very important and loving niche for itself in the woodworking community.Completely Arbortrary is produced and hosted by Casey Clapp and Alex CrowsonSupport the pod and become a Treemium MemberFollow along on InstagramFind Arbortrary merch on our storeFind additional reading on our websiteCover art by Jillian BartholdMusic by Aves and The Mini-VandalsSee Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.
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