Since 2004, citizen scientists in Torreya Guardians have been helping a glacial-relict endangered tree, Florida Torreya, move to cooler regions of the eastern USA. This video begins with a celebration of the 1,000+ seeds our grower in Ohio produced Autumn 2023 in the little torreya orchard he had planted in his front yard - quite an accomplishment! The rest of the video is a presentation by the group's founder, Connie Barlow, of the long and shifting history of scientific speculation and (sometimes faulty) assumptions about the ultimate cause(s) of this ancient conifer's sudden demise in its tiny historical range in Florida.
Motivated by the July 2023 adoption of a new regulation permitting the agency in charge of the Endangered Species Act (ESA) to expand recovery efforts beyond the "historical range" - especially if climate change had already damaged prospects there - Connie began a scholarly search of new papers that might offer guidance for Florida Torreya. What she found was a "paradigm shift" (beginning around 2016) that offered new and compelling scientific reasons for the ESA implementers to follow the lead of this citizen group in "assisted migration" poleward as a way to help this tree regain its ability to fight native diseases. Central to this new understanding is the discovery that all plant tissues - including seeds - harbor beneficial fungal and bacterial partners: what is now called the Plant Microbiome and the Seed Microbiome.
The new webpage Barlow posted that entails this history of "Endangerment Causes" is primarily a chronological list of papers on this topic, with long excerpts:
www.torreyaguar...
Timecoded table of topics below:
00:25 - View 1,200 seeds from Ohio and where Connie will "winter stratify" them all in pits on a forest slope
01:58 - Two techniques Barlow uses to wild-plant torreya seeds to reduce chances of herbivory by deer.
02:28 - Video of Fred Bess's torreya orchard in Cleveland.
04:13 - The rest of the video explores the history and shifting understanding of cause(s) limiting Florida torreya's range during the Ice Ages and then provoking diseases to ramp up mid 20th Century. A lengthy new webpage Barlow created is read or summarized by Barlow, with periodic breaks for additional discussion and examples. The tagline for the page is: "From environmental trigger hypotheses of multiple pathogens to focus on a single fungus - and back to climate change stress as ultimate cause."
04:37 - Foundational understanding of Florida torreya as a "glacial relict" unable to return (ie., float back upstream) to the Appalachian Mountains at the end of the Ice Age.
07:46 - July 2023 a new regulation authorizes assisted migration of endangered species
09:05 - The new endangerment causes webpage has papers organized in 6 phases.
14:30 - Reading and commentary on the "Purpose" section of the webpage
30:14 - "Summary of the Six Phases":
(1) 30:24 - Observer pathologies and identify disease agents
(2) 31:46 - Search for an environmental cause
(3) 34:46 - Focus on Fusarium sp. as lethal pathogen
(4) 41:12 - Fungal endophytes can be beneficial
(5) 44:46 - Fusarium torreyae in "all seeds" confirms core mutualism
(6) 46:58 - Mutualists become pathogens when stressed by climate change
43:25 - Quick scroll-through of the titles of papers (with excerpts and some commentary) in each of the 6 phases.
Phase 1 - 55:31
Phase 2 - 56:24
Phase 3 - 57:20
Phase 4 - 1:05:22
Phase 5 - 1:06:50
1:08:42 Closing with film of Barlow in the forest of Michigan talking to her young torreya seedling.
1:10:03 - Slides of this video title page and several of the previous videos in the Torreya Guardians series:
"Torreya Guardians Assisted Migration" playlist on youtube:
• Torreya taxifolia - as...
Torreya Guardians webpage that lists and summarizes all 37 videos:
www.torreyaguar...
26 авг 2024
