Completely Arbortrary

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.

Episodes

April 30, 2026 65 mins

Originally aired 12/23/21


Join the Cone Club, our snail-mail botanical sticker club to support the pod. Link in the bio!


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 ...

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Originally Aired 10/27/2022

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-...

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Mark as Played
April 16, 2026 57 mins

Originally aired 12/07/2023

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-...

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Mark as Played
April 9, 2026 58 mins

Originally aired 1/27/2022

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...

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Mark as Played

In our final mainline episode of Completely Arbortrary, we revisit the tree that started it all: the Douglas-fir (Pseudotsuga menziesii).

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

Mus...

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Mark as Played
March 26, 2026 75 mins

In our penultimate episode of Completely Arbortrary (as we know it), we discuss the wild whiskey cherry (Prunus serotina) and its many wooden accolades.

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

Support the pod and become a Treemium Member

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Find Arbortrary merch on our store

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Cover art by Jill...

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Mark as Played
March 19, 2026 10 mins

Alex is unexpectedly out this week so you get a bunch of ums and uhhs from Casey along with an audio essay about desert trees!

See 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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March 12, 2026 73 mins

Be one with the land (and also learn teleportation) with Anastasianism, a religion centered around the Siberian stone pine (Pinus siberica).

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

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Cover art by Jillian Barthold

...

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Mark as Played

260 episodes and 5 years later, and Casey has found an apple he loves, (Malus hupehensis), which he dubs by far the most interesting apple in 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 Jill...

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Mark as Played
February 26, 2026 70 mins

Fog: the coast redwood's strongest ally through a process called folial uptake.

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...

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Mark as Played
February 19, 2026 63 mins

Don't go reinventing the wheel tree (Trochodendron aralioides), it certainly isn't.

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 h...

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Mark as Played
February 12, 2026 90 mins

You’ve heard of old growth forest… but how about old growth woodland? For more info, ask the western juniper (Juniperus occidentalis), a tree that is helping to redefine the meaning of old growth. Then, we play a brand new game!

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

Support the pod and become a Treemium Member

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Find Arbortrary merch on our store

Find additional rea...

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Mark as Played
February 5, 2026 68 mins

A tree that lacks nothing… except for name recognition: the superb schima (Schima superba) (yes, that is its real name.)

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 http...

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Mark as Played
January 29, 2026 79 mins

Forget everything you thought you knew about conifers, and make way for the celerytop-pine (Phyllocladus aspleniifolius) with leaves and cones like no other, and raises the question “what is a conifer”?

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 addit...

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Mark as Played
January 22, 2026 60 mins

When the emerald ash borer came to North America, few ashes survived. But one native species, the blue ash (Fraxinus quadrangulata), survived. How did this lucky survivor beat the odds?

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 Bar...

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Mark as Played
January 15, 2026 86 mins

Today we discuss our flexible friend the limber pine (Pinus flexilis) and its curious co-evolutionary relationship with, you guessed it, BIRDS.

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...

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Mark as Played
January 8, 2026 70 mins

Welcome to Season X of Completely Arbortrary, our final hoorah! To begin the end, we talk about senses of smell and the Scots pine (Pinus sylvestris).

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

Support the pod and become a Treemium Member

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Find Arbortrary merch on our store

Find additional reading on our website

Cover art by Jillian Barthold

Music by Aves and The Mini-Van...

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Mark as Played

It's been 5 years of weekly tree podcasts, but after this final season, Casey and Alex will be moseying on to the next chapter for an extended hiatus. Buckle up for THE FINAL SEASON of Completely Arbortrary.

See 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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Mark as Played

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

Follow...

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Mark as Played

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 Th...

Listen
Watch
Mark as Played

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