Assisted Migration of Florida Torreya
to Leelanau Peninsula of Michigan
40 forested acres owned by Liana May
conservation easement via Leelanau Conservancy

   INTRODUCTION by LIANA MAY: The property entails 40 acres of sugar maple-beech-ash mesic northern forest on upper slopes of large end moraine, various aspects and slopes ranging from 0 to >30%. Managed for conservation, with some firewood production for personal use. Within a large continuous forest of several thousand private and public (national park) acres. See attached Forest Management Plan.
    I am already experimenting with some assisted migrations and restoration, as my forest is mostly beech and ash that are dying from the ash borer and beech bark disease.
    We have very steep north, east, and west facing slopes (>30%). We also have gentle south facing slopes. It's a big end moraine (see the Topo map in the management plan), so soils are unsorted till with a very lush understory. Moisture ranges from dry topslopes to mesic slopes to wet lowslopes with springs and seeps. The larger valley that we sit atop faces northeast, but we are fairly protected from dominant north-west winds. I see the three best options for planting as 1) the seepage area on steep slopes that face north, 2) the gentle south-facing slope, or 3) the deep and steep N-S running ravine. I put these on the attached Topo map. 

SEEDS VIA TORREYA GUARDIANS: 240 seeds mailed April 2017 from the donation by Frank Callahan of Fall 2016 seeds harvested from the pair of Torreya taxifolia trees on his property in Medford, OR.

SEED PLANTING DOCUMENTATION: Liana reported by email 15 April 2017: "Planted most of the seeds out today in a warm thunderstorm, eight groups across three locations with different aspects and slightly different wetnesses. I planted 25 in pots as well, since there were so many mole tunnels, even on the steepest slopes. I planted all seeds 4 to 6 inches in depth. I'm going to raise the potted ones at my house and see how they germinate, and if they do well I'll plant out with tree tubes."

EXCERPT FROM FOREST MANAGEMENT PLAN: ... Biodiversity conservation is the landowner's primary interest for the long-term functionality of the parcel in the regional landscape. Planting locations will be marked with stakes and flagging, and GPS located. Species currently identified for enhancement include the following:

Panax quinquefolius - This forest parcel is prime habitat for Michigan-threatened American ginseng. 500 pre-stratified seeds will be planted in a few locations across the property in May of 2017 and monitored.

Taxus canadensis – Canadian yew will be re-introduced to this parcel and fenced to prevent herbivory.

Torreya taxifolia - Assisted migration of federally endangered species from Florida in collaboration with Torreya Guardians ( Endemic to northern mesophytic steepheads in the Florida panhandle, it is theorized this tree once had a wide range including northern hardwood forests: "The dominant trees in a torreya ravine [in Florida] are red maple, southern sugar maple, beech, magnolia, basswood, elm, torreya, and sabal palm. Most of these species have northern affinities and are more commonly found in Appalachian cove forests. Other plants found in torreya ravines also represent species of northern affinities such as strawberry bush, hydrangea, and redbud." (Charles Wharton, The Natural Environments of Georgia, 1978). Therefore, assisted migration experiments are currently taking place to establish this species outside of the known historically native range in a hope to stage the U.S. population for recovery in the face of climate change. Plant in steephead slopes and protected valleys.

JULY 2018 REPORT: Connie Barlow visited the forest site with Liana May and Alison Horton on July 26. A total of three tiny seedlings were VIDEO-documented, as below:

VIDEO 25: Assisted Migration of Florida Torreya to Michigan - Leelanau Peninsula (15 minutes)

   Germination success in planting seeds directly into a rich forest habitat is show-cased during a field visit to our northern-most planter in Michigan (near Traverse City). Liana May is a professional botanist who "free-planted" seeds directly into the conservation easement on her 40 acres of forested property. Thankfully, by the time she received the seeds, other Torreya Guardians had confirmed an ideal way to foil rodent predation: plant the seeds 4 to 6 inches deep. Liana followed those directions, so we are expecting a satisfying proportion of the seeds to produce seedlings by fall of 2019.


18 OCTOBER 2018 REPORT: by Liana May, "We now have about 12 seedlings, 1 to 3 across most of the plots in the Echo Valley forest."


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