First Half of May

• Cinnamon fern (fiddleheads emerging)

• Goldthread

• Herb emergence on hummocks in wooded fen zones

• Kidney-leaved violet

• Larch or Tamarack needles starting to emerge

• Leaf out by woody species (general; started in late April)

• Leatherleaf

• Red maple (flowers; flowering may start late April)

• Sensitive fern (fiddleheads emerging)

• Skunk cabbage (starting in early April, the spathes emerged, and flowering began; now, the spathes are full size, and flowering near-complete; leaf buds opening, and leaves expanding rapidly)

• Snowshoe hare (partly/mostly change to summer pelage)

• Speckled alder (flowers ending; began flowering in early April)

• Swamp fern (fiddleheads emerging)

• Royal fern (fiddleheads emerging)

About this calendar
The calendar is arranged in half-month intervals rather than specific ranges of dates because of limitations in our data from the first three years of observation.  As more data are obtained, the calendar will be refined and expanded. We hope to add much more seasonal information on animals (vertebrates and invertebrates).

You can help by reporting your seasonal natural history observations at the boardwalk to Ron Davis at ronald.davis@umit.maine.edu or 1-207-866-4786.  Indicate the date(s) of your observation(s) and the habitat(s) where the species or event(s) was/were observed. 

Flowering dates apply to the large majority of individuals of a species present along the boardwalk;  a few individuals may flower even earlier or later than listed.  Many seasonal events vary from year to year depending on the weather and ground conditions.  The Latin name and habitat (vegetation zone) where vascular plant species occur are indicated on this website.  See Vascular Plants .

Second Half of May

• Bogbean

• Bog laurel

• Bog rosemary  

• Bunchberry

• Canada mayflower

• Cinnamon fern (leaves expanding)

• Goldthread

• High bush blueberry

• Intermediate sundew (plant emerging and enlarging)

• Kidney-leaved violet

• Leaf out by woody species (general; largely completed by end of month)

• Mountain fly honeysuckle

• Mountain holly

• Rhodora

• Round-leaved sundew (plant emerging and enlarging)

• Royal fern (leaves expanding)

• Sensitive fern (leaves expanding)

• Skunk cabbage (spathes prominent; leaves expanding rapidly)

• Starflower

• Swamp dewberry

• Swamp fern (leaves expanding)

• Tall cotton-grass (flowers; white-bristled fruits persist to the fall)

• Tussock cotton-grass (flowers; white-bristled fruits persist to the fall)

• Wild calla

First Half of June

• Black chokeberry

• Blue flag iris

• Bogbean

• Bog laurel

• Bristly rose

• Bunchberry

• Canada mayflower

• Cinnamon fern (leaves expanding; cinnamon spore-producing stalk developing)

• High bush blueberry

• Intermediate sundew (plants reaching full size)

• Labrador tea

• Pitcher plant

• Rhodora (flowers ending)

• Round-leaved sundew (plants reaching full size)

• Royal fern (leaves expanding; spore-producing part maturing)

• Sensitive fern (leaves expanding; spore-producing stalk developing)

• Sheep laurel

• Skunk cabbage (leaves becoming full size)      

• Swamp fern (leaves expanding)

• Three-leaved false Solomon's seal

• Wild calla

Second Half of June

• Blue flag iris

• Cinnamon fern (leaves full size; cinnamon spore-producing stalk mature)

• Grass-pink (orchid)

• Intermediate sundew

• Pitcher plant (flowers; sepals and fruits persist all summer)

• Round-leaved sundew

• Royal fern (leaves full size; spore-producing part mature)

• Sensitive fern (leaves full size; spore-producing stalk mature)

• Sheep laurel

• Small cranberry

• Swamp fern (leaves full size)

• Three-leaved false Solomon's seal

• Tufted loosestrife

 First Half of July

• Grass-pink (orchid)

• Naked bladderwort

• Swamp candles

• Tufted loosestrife

• White-fringed orchid

• Winterberry

 Second Half of July

• Boneset

• Naked bladderwort

• Tall meadow-rue

 First Half of August      

• American water hore-hound

• Aster (wetland species)

• Naked bladderwort

 Second Half of August

• Aster (wetland species)

• White turtlehead              

First Half of September

• Aster (wetland species)       

Second Half of September

• Cinnamon fern (turning orange-yellow)

• Winterberry (berries turning orange)

 First Half of October

• Huckleberry (reddening foliage)

• Larch or Tamarack (needles turning gold)

• Red maple turning color

• Winterberry (berries turning orange-red)

Second Half of October

• Larch or Tamarack (needles smoky gold, and starting to fall)

• Red maple leaves bright red

• Winterberry (berries red)

First Half of November

• Larch or Tamarack (golden needles falling)

• Red maple leaves falling

Second Half of November

(The boardwalk closes in late November, the exact  date depending on weather and surface conditions)    

• Bog turning brown

• Ground frost starting to form

• Leaf fall largely complete

• Possible ice formation on boardwalk (slippery)

• Possible snowfall