Completely Arbortrary
Completely Arbortrary
<p>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.</p>
- 1 hour 10 minutesAre You There, Fog? (Coast Redwood 2)
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
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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.
26 February 2026, 8:00 am - 1 hour 3 minutesReinventing the (Wheel Tree)
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 https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.
19 February 2026, 8:00 am - 1 hour 30 minutesEven Older Growth (Western Juniper 2)
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
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.
12 February 2026, 8:00 am - 1 hour 8 minutesRenaissance Tree (Superb Schima)
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 https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.
5 February 2026, 8:00 am - 1 hour 19 minutesCones on the Spectrum (Celerytop-Pine)
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 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.
29 January 2026, 8:00 am - 1 hour 52 secondsEvolutionary Naïveté (Blue Ash)
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 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.
22 January 2026, 8:00 am - 1 hour 26 minutesBird Influence (Limber Pine)
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 Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.
15 January 2026, 8:00 am - 1 hour 10 minutesBurning Hot Fresh Root News (Scots Pine)
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
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.
8 January 2026, 8:00 am - 50 minutes 41 secondsIt's The End of Completely Arbortrary (As We Know It)
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.
1 January 2026, 8:00 am - 1 hour 17 minutesHow Water Moves Through Trees (Oyster Bay-Pine)
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 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.
25 December 2025, 8:00 am - 1 hour 18 minutesUnderplanted, Underrated, Underappreciated (Japanese Pagodatree)
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.
18 December 2025, 8:00 am - More Episodes? Get the App