Field Trip Through a Typical Maine Raised Bog

 

 

Field Trip through a Typical Maine Raised Bog (Peatland)

 

Robert Zottoli

rzottoli@roadrunner.com

 

Professor Emeritus

Fitchburg University

Fitchburg Massachusetts

 

 

 

 

 

Introduction:

 

 

The most memorable field experience for most of my ecology students was a trip to a local floating bog (Mud Pond, Ashburnham Massachusetts). The vegetation along the outer bog edge literally floats on top of the water. Students were in awe as they walked across the undulating bog surface. Usually we ran a transect line from forest to water’s edge and recorded the presence and relative number of bog species along the line. Participants were encouraged to research each of the species and relate this information to plant distribution. Emphasis was placed on how plant species were adapted to live in this unique, nutrient poor environment. My interest in peatlands, especially raised bogs, has followed me into retirement. It is my desire to pass along this interest to a wider audience. Digital photographs throughout the growing season accompany brief written descriptions of selected bog plants as well as a few of their culinary and medicinal uses. Finally, some of the adaptive features that help a select few of the species to survive or thrive on the bog are briefly mentioned.

The web program was created to provide a field experience for those unable to reach the Bog or those who would like to review typical Bog species before going into the field. Please let me know if the program meets your needs. It would also be helpful if you could make suggestions on how to improve the program. Send comments to me at: rzottoli@roadrunner.com

Raised bogs are peatlands whose surface is raised above their outer edges due to accumulation of dead vegetation. The only sources of water are rain, snow and fog. Refer to Johnson (1985) for additional information on raised bogs. They are often surrounded by a moat where water tends to accumulate often making it difficult to reach the bog surface. There tends to be a gradient of low moisture and low nutrient levels at the bog center to higher moisture and higher nutrient levels at the bog edge; here shrubs form dense, tall thickets.

The bog environment is highly acidic. Acid conditions are for the most part maintained through the metabolism of dominant sphagnum mosses. Sphagnum mosses take up positively charged ions such as Calcium and Phosphorus and in the process release hydrogen ions into the surrounding water making it more acidic. High acidity inhibits bacterial and fungal decomposition of dead plant matter that accumulates at the end of the growing season, allowing it to build up over time eventually forming peat. Bacterial and fungal decomposition is an essential process that allows recycling of nutrients such as nitrogen and phosphorus necessary for new plant growth. When this process is inhibited in the bog for example, plant growth is inhibited. Bog plant strategies for overcoming nutrient limitation are discussed in general below and are offered in some of the species descriptions.

Http://en.wikipedia.org/wiki/Sphagnum_moss

Three of the mechanisms that bog plants have evolved to cope with low nutrient levels are:

1. Slow Growth: Trees such as Black Spruce (Discussed in The Bog Trees section) that grow on the heath tend to be shorter (Dwarf) than those of the same age growing at the bog edge. Note how the trees in the photograph below, diminish in height from right to left. How does this relate to nutrient use?

Http://en.wikipedia.org/wiki/Picea_mariana

 

 

2. Leaf Retention: Evergreen plant species such as Leatherleaf (The Bog Family Ericaceae) retain their leaves for more than one season. How does this help plants cope with low nutrient levels?

 Http://en.wikipedia.org/wiki/Leatherleaf

3. Carnivory: Several bog plants, such as the Pitcher Plant and Sundew supplement photosynthesis by capturing and digesting animal prey. How does this help these plants cope with low nutrient levels?

 Http://en.wikipedia.org/wiki/Sarracenia_purpurea

4. During periods of moderate to heavy rainfall, standing water accumulates on the bog surface. The low oxygen content in standing water (compared to that in the atmosphere) makes it difficult for bog plants to extract enough oxygen for their metabolic needs. Low oxygen levels also inhibit bacterial and fungal decomposition. Two of the mechanisms that bog plants use to raise oxygen levels or acclimate to low oxygen levels are:

a.  Development of roots that lie on or above the bog surface where atmospheric oxygen is readily available.

 Http://en.wikipedia.org/wiki/Eriophorum_vaginatum

b. Slow Growth: Trees such as Black Spruce , that grow on the heath,  tend to be shorter (Dwarf) than those of the same age growing at the bog edge. How does this relate to nutrient use?

 

The journey begins in the wet woodland forest surrounding the bog. The woodland forest often merges into a relatively narrow, wet, bog border followed by the bog itself. Plant species typical of each area are discussed below. Within the discussion of each zone, plants are listed by group (ferns, trees, orchids, etc.) and within each group by family name, in alphabetical order. Plant species are not necessarily restricted to the zone in which they are described.  Lists of plant species arranged in alphabetical order by family, species name, and common name are provided. 

Connections to selected websites are listed beneath the scientific name of each species. Wikipedia  (Http://en.wikipedia.org/wiki/Home_Page) , a free encyclopedia, generally provides more specific information about the species in question. Keep in mind that anyone can edit information on this site. The Plants Database published by the U.S. Department of Agriculture (http://plants.usda.gov/java) makes available a wealth of information on most plant species as well as “related websites” and additional “species accounts and images” in the “more accounts and images” section at the bottom of the page.

 

I have identified and photographed many of the common raised bog species throughout the growing season at the following locations:

Appleton Cedar Swamp: 044°26’13.5”N, 069°16’7.2”W
Corea Heath: 044°24′ 38″N, 067°59′ 24″W
Garcelon Bog: 044°05’46.6”N, 070°10’54.9”W
Great Sidney Bog (Bog Rd. Augusta): 044°23”N, 069°46’5”W
Orono Bog Boardwalk (Tripp Dr. Bangor): 044°51’45″N, 068°43’42″W
Roosevelt Campobello International Park, Eagle Hill Bog: 044°52’15.4”N, 066° 57’27.0”W
Saco Heath: 043°32’52.1”N, 070°28’22.6”W
Shaker Bog: 043°59’42.9”N, 070°51’59.08”W
West Quoddy Head Bog: 044°48’56.9”N, 066°57’25.4”W

Digital images were taken at different times throughout the seasons by Dr. Robert Zottoli. Most of the photographs were snapped with Nikon D200,D300 or D7000 SLR digital cameras, all equipped with a 60 mm AF Micro Nikkor 1:2.8 D lens. The majority of images were enhanced and reduced in size within Adobe Photoshop CS4 or CS5. The web site was constructed using Dreamweaver CS4 and CS5 and WordPress. Digital images provided on this web site may be reproduced for non-commercial, personal, educational or scientific purposes only. Copying or redistribution in any manner for personal or corporate gain is not allowed without written permission from Robert Zottoli (rzottoli@roadrunner.com). Use the following format to identify pictures and give credit to photographer Robert Zottoli: https://rzottoli.wordpress.com

Plant species were identified using keys provided in Hinds (2000) and Magee and Ahles (2007):

Hinds, Harold R. 2000. Flora of New Brunswick. 2nd. Ed. Biology Department, University of New Brunswick. ISBN1-55131-015-5. 699 pp.

Magee, D.W. and H.E. Ahles, 2007. Flora of the Northeast. A manual of the vascular flora of New England and adjacent New York. 2nd Ed., University of Massachusetts Press, Amherst. 1214 pp. ISBN 13: 978-1-55849-577-7.