Primula laurentiana Fernald:
Canada (North America)
United States (North America)

Global Range: Eastern North America from southern Labrador, New Foundland to western Quebec to Nova Scotia. In the United States, found in eastern and northern Maine.

Comments:

The two most salient features of the habitat of P. laurentiana on Great Wass Island are full sunlight and minimal competition. Hence it most characteristically grows in thin soils bordering headlands or ledges or in pockets of sandy or gravelly soil. May be a calciphile. While it usually grows in the vicinity of Sedum rosea, this taxon is capable of colonizing fissures in the headland rocks closer to the ocean spray than P. laurentiana. Associated species of P. laurentiana include Agrostis stolonifera, Campanula rotundifolia, Carex canescens, C. viridula, Deschampsia flexuosa, Euphrasia canadensis, E. randii, Festuca rubra, Iris hookeri, Juncus filiformis, Lomatogonium rotatum, Plantago juncoides, Triglochin maritima, and Viola septentrionalis.

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: 81 to >300

Comments: 8 extant EOs in ME.

This data refers to the N. American P. laurentiana which Kartesz synonymizes with the European P. farinosa.

P. laurentiana is self-compatible; plants enclosed in small-mesh screenin from before flowering to well after the completion of flowering set fruit regardless of whether or not the self-pollination was done with a camel's hair brush or naturally. The bright petal color and faint fragrance would appear to be adaptations for insect pollination. During warm sunny weather, five species of insects (a butterfly, 2 bees and 2 syrphid flies) were observed visiting a large Primula population at Red Head on Great Wass Is. The larger of the two syrphids clearly spent the most time on Primula flowers. Based on the abundance of Primula pollen in the gut of one individual of this large syrphid (collected after it had spent about 4 minutes on 10 flowers) and the absence of nectar, pollen appears to be the major pollinator award. These syrphids did not visit other species flowering at the same time (in particular, Sedum rosea and Viola septentrionalis). It is not known how important these pollinators are to cross-pollination in P. laurentiana.

It is clear that this species is reproducing successfully by seed on Great Wass Is. There are about 10,000 flowering individuals on the island and perhaps 10 times as many total individuals when juveniles and non-reproductive plants are included.

Canada

Rounded National Status Rank: NNR - Unranked

United States

Rounded National Status Rank: NNR - Unranked

Rounded Global Status Rank: G5 - Secure

Reasons: Range is in Eastern North America from southern Labrador, New Foundland to western Quebec to Nova Scotia. In the United States, it is found in eastern and northern Maine. Rare in the United States. Appears to be secure in Canada. It most characteristically grows in thin soils bordering headlands or ledges or in pockets of sandy or gravelly soil. It may be a calciphile.

Comments:

On Great Wass Is., P. laurentiana grows where hikers, beach-combers, and nature lovers are likely to walk. Trampling by humans does not seem to have hurt Primula populations. At this time, other threats such as animal predation, habitat loss due to succession, or displacement by other plant sp. do not appear to be serious concerns.

Restoration Potential:

Although P. laurentiana is capable of extensive reproduction by seed, not enough is known about germination requirements or the soil needs of seedlings to predict how population size would respond to soil changes associated with human interference.

Preserve Selection and Design Considerations:

TNC might prevent the building of trails to certain parts of Great Was Is. (specifically the western shore where there are isolated populations of P. laurentiana).

Management Requirements:

P. laurentiana occupies vegetationally stable habitats in eastern Maine. Short-term reductions in population size are most likely to result from human activity (trampling, development).

Monitoring Programs: A.J. Lewis has been monitoring Primula on several Maine islands as part of a floristic study of Machias Bay.

Management Research Programs:

Maine Field Office/ The distribution, ecology, and reproductive biology of Primula laurentiana Fernald (Primulaceae) in the Great Wass Island Archipelago/ a Maine Small Grants Research project, 1983 by C.S. Campbell and N.C. Famous.

Biological Research Needs:

(1) How does P. laurentiana respond to trampling?

(2) How narrow is the niche of P. laurentiana? or how narrowly adapted is it to limited competition and soil character- istics like pH, aeration, and organic content?

(3) How are seeds dispersed?

(4) What conditions are necessary for germination?

(5) Are there mechanisms to promote outcrossing and thereby population variability?

(6) How much seed production occurs in natural populations?

Some of these questions will be at least partially answered by of the currently on-going studies. Others can be answered by general observations and soil studies.

Needs: None.

Stewardship Overview:

Demographic studies of populations of P. laurentiana on off-shore islands in Maine could be very informative about the factors controlling the distribution and abundance of this species. The current studies should also contribute to the knowledge of the biology of this species.