Completely Arbortrary

Latest Episodes:

How Water Moves Through Trees (Oyster Bay-Pine) Dec 25, 2025

Show notes

Turgor pressure, negative pressure, vessels and tracheids, embolisms… It’s a fact-packed Christmas Day episode of Completely Arbortrary, featuring the Oyster Bay-pine (Callitris rhomboidea). This drought tolerant tree has a surprising mechanism for keeping its water closely guarded. Merry Christmas!

Completely Arbortrary is produced and hosted by Casey Clapp and Alex Crowson

Support the pod and become a Treemium Member

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Cover art by Jillian Barthold

Music by Aves and The Mini-Vandals

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Underplanted, Underrated, Underappreciated (Japanese Pagodatree) Dec 18, 2025

Show notes

Underrated, underplanted, underappreciated… so why isn’t the Japanese pagodatree (Styphnolobium japonicum) a more popular as a street tree in our urban forests?

Completely Arbortrary is produced and hosted by Casey Clapp and Alex Crowson

Support the pod and become a Treemium Member

Follow along on Instagram

Find Arbortrary merch on our store

Find additional reading on our website

Cover art by Jillian Barthold

Music by Aves and The Mini-Vandals

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Ivory & (Ebony) Dec 11, 2025

Show notes

work together in perfect harmony (guitar reference). Today, learn all about the ebony (Diospyros ebenum), it's typical path through capitalism, and the guitar luthier who gave it back to the world.

Completely Arbortrary is produced and hosted by Casey Clapp and Alex Crowson

Support the pod and become a Treemium Member

Follow along on Instagram

Find Arbortrary merch on our store

Find additional reading on our website

Cover art by Jillian Barthold

Music by Aves and The Mini-Vandals

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

The Odysseed (Lotus Tree) Dec 04, 2025

Show notes

Hop aboard the good ship Odyssey to make for the island of the lotus tree (Diospyros lotus). But, could this be a case of mistaken idenitree?...

Completely Arbortrary is produced and hosted by Casey Clapp and Alex Crowson

Support the pod and become a Treemium Member

Follow along on Instagram

Find Arbortrary merch on our store

Find additional reading on our website

Cover art by Jillian Barthold

Music by Aves and The Mini-Vandals

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Holiday Merch Sale + Urban Trees and Racism Nov 27, 2025

Show notes

As we take a quick break we're here to remind you that our holiday merch sale ends ON BLACK FRIDAY, and reintroduce you to our talk on urban trees and racism.

Completely Arbortrary is produced and hosted by Casey Clapp and Alex Crowson

Support the pod and become a Treemium Member

Follow along on Instagram

Find Arbortrary merch on our store

Find additional reading on our website

Cover art by Jillian Barthold

Music by Aves and The Mini-Vandals

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

BONUS EPISODE: Fungus in the Fall Nov 20, 2025

Show notes

As the boys take a much needed break from the wild world of modern podcasting, they present to you the audio from a 2023 livestream entitled Fungus in the Fall.

Completely Arbortrary is produced and hosted by Casey Clapp and Alex Crowson

Support the pod and become a Treemium Member

Follow along on Instagram

Find Arbortrary merch on our store

Find additional reading on our website

Cover art by Jillian Barthold

Music by Aves and The Mini-Vandals

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Splitting Facts (Weeping Juniper) Nov 13, 2025

Show notes

So many junipers, so little time. So let’s pick one! How about the weeping juniper (Juniperus flaccida)? Buckle up, it’s gonna be a bumpy one.

Completely Arbortrary is produced and hosted by Casey Clapp and Alex Crowson

Support the pod and become a Treemium Member

Follow along on Instagram

Find Arbortrary merch on our store

Find additional reading on our website

Cover art by Jillian Barthold

Music by Aves and The Mini-Vandals

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Goin' Thig Mode (Fraser Fir) Nov 06, 2025

Show notes

The boys are joined by their first ever third host to discuss goin' thig mode with thigmomorphogenesis and the Fraser fir (Abies fraseri). Then, a test of Casey's binomial spelling skills with The Spelling Tree.

Completely Arbortrary is produced and hosted by Casey Clapp and Alex Crowson

Support the pod and become a Treemium Member

Follow along on Instagram

Find Arbortrary merch on our store

Find additional reading on our website

Cover art by Jillian Barthold

Music by Aves and The Mini-Vandals

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.

Deal with the Devil (Bigleaf Magnolia) Oct 30, 2025

Show notes

BEEware of the bigleaf magnolia (Magnolia macrophylla). This tree made such a strong alliance with beetles, that any other insect trying to get in gets KILLED. Then we play a Halloween edition of Family Tree!

Completely Arbortrary is produced and hosted by Casey Clapp and Alex Crowson

Support the pod and become a Treemium Member

Follow along on Instagram

Find Arbortrary merch on our store

Find additional reading on our website

Cover art by Jillian Barthold

Music by Aves and The Mini-Vandals

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.