Past Peak

In the area around the City of Green Bay many trees have lost all or most of their leaves, especially the commonest and most abundant species such as green ash (Fraxinus pennsylvanica), box elder (Acer negundo), and cottonwood (Populus deltoides). Other species generally leafless now include: white birch (Betula papyrifera), quaking aspen (Populus tremuloides), and wild cherries (Prunus serotina and Prunus virginiana).

Species still holding leaves include the invasive buckthorns (Rhamnus cathartica and Frangula alnus), Norway maple (Acer platanoides) and to a lesser degree silver maple (Acer saccharinum). The oaks also tend to hang onto their leaves, even after they turn brown (see Nov. 4). The photo at left shows still-green leaves of European buckthorn under the mostly bare branches of other species. If you look carefully, you may also notice green leaves still on the branches of a crack willow (Salix fragilis, another alien species) behind the other trees, toward the right side.


Point au Sable Phragmites Burn

The Point au Sable Natural Area is an unmodified estuarine wetlands, one of the few in the Lake Michigan ecosystem. This area plays a very important role for the migratory birds passing through. This is the main reason why this area has stayed protected from development. In recent findings, it was shown over 200 different bird species in one year have stopped to enjoy the Point au Sable Natural Area. For more information about the Point au Sable Natural Area click on the link

Recently the Point au Sable Natureal Area was burned in an effort to try and stop the Phragmites invasion. Phragmites australis, also known as the common reed, is an exotic invasive species. It can grow up to 3-4 meters.



 It was estimated the flames reached 75-100 feet. If you look closely you can see a burn crew member just at the base of the Phragmites.








According to the Arboretum Project Coordinator, Joshua Martinez, “the lagoon should be a mixture of open water, submerged aquatic plants, emergent marsh, cattail marsh, and sedge meadow.  The Lagoon system is ever changing with water levels of the great lakes (more specifically the bay).  As a result, Point au Sable was historically a heavily disturbed site, not because of people but rather because of water level cycles of the great lakes.  Phragmites was present on the site in the last flooding of the lagoon in 2000, and once the water levels had receded the Phragmites was able to spread very fast because of its growth patterns of stolons and rhizomes.  This was because the soil surface of the lagoon was exposed with little vegetation on it and allowed the Phragmites to spread fast with little resistance from native plant competitors.  In addition, the lakes levels have not been following their typical water level cycle, and have been staying low for longer than expected and provides great potential for Phragmites to spread aggressively.”

For more detail on Phragmites australis and it’s growth patterns click on the link


The final product after the burn. We are now able to see straight across the lagoon.










 Looking at the photos below we can see that Phragmites has greatly increased as the water levels have decreased over the years.

Lagoon 1999
Lagoon 2012










Phragmites must be monitored because they “threaten the ecological health of wetlands as well as the Great Lakes coastal shoreline.” Phragmites can

  • over take native plants and animals
  • block shoreline views
  • reduce access for swimming, fishing, and hunting
  • create fire hazards from dry plant material

One of the most effective procedures to control the Phragmites population is to use an integrated pest management approach. This approach includes

  • treating the area with herbicides
  • mechanical removal (cutting, mowing, burning)
  • annual maintenance


We have taken the first steps in burning Phragmites and we will continue to treat the Point au Sable area by using herbicides to control the Phragmites population.



Michigan Department of Environmental Quality,4561,7-135-3313_3677_8314-178183–,00.html

Keith White Priaire is Alive with Color!

The summer months are a time when our prairies and grasslands come alive with color. In the Cofrin Memorial Arboretum, on the UW—Green Bay campus, a prairie was established by botanist Dr. Keith White and his students in 1974. This demonstration of mesic prairie, where the soils are moderately damp, and dryer oak opening habitats provides students an opportunity to experience these ecosystems firsthand, without having to travel off-campus. It is now a popular walking and biking destination for community members and students who need a break from the stress of classes and work. Our main objective on this prairie is to manage for plant diversity that will support other native species including increasingly rare grassland nesting birds.

If you have a chance to walk the trail through the prairie you will see many unique plant species in flower during the mid-summer.  As in all prairies, the plant community in the Keith White Prairie is dominated by a few grass species including Big Bluestem (Andropogon gerardii), Switchgrass (Panicum virgatum), and Indian grass (Sorghastrum nutans). Grasses are wind pollinated and so do not typically have large showy flowers. Instead, grasses have small inflorescences on spikes that become showier in the late summer and fall as the seeds mature.

Purple and yellow Coneflower (upper left), Prairie Dock (upper right), Culver’s root (lower left), and Compass Plant (lower right).


The colorful jewels of the prairie are the forbs or showy flowering plants.  These plants produce flowers that attract insect or hummingbird pollinators and are often showy and colorful. Flowers in the prairie are primarily yellows and purples, which attract insects like bees and butterflies.  The most common tall plants you will see in flower in mid-July through August include  Compass Plant (Silphium laciniatum), Prairie Dock (Silphium terebinthinaceum), Rosinweed (Silphium integrifolium), many species of Goldenrods (Solidago Spp.), Black-eyed Susan (Rudbeckia hirta), Purple Coneflower (Echinacea purpurea), Rattlesnake Master (Eryngium yuccifolium), Culver’s Root (Veronicastrum virginicum), Yellow Coneflower (Ratibida pinnata), and Wild Bergamot (Monarda fistulosa).  

Nodding Pink Onion (upper left), Purple Prairie Clover (upper right), White Prairie Clover (lower left), and Spotted Bee Balm (lower right).


When the prairie was planted, careful consideration was made to match different plants to their preferred soil conditions (e.g. water moisture, productivity).  As a result, the numbers and types of flowers vary in different parts of the prairie, even from year to year, in response to weather conditions.  A careful observer will be rewarded with a display of flowers that bloom below the grasses and tall  forbs.  Some of the species to look for are Purple Prairie Clover (Dalea purpurea) and White Prairie Clover (Dalea candida), which are adapted to dry soils; and Bush Clover (Lespedeza capitata), Spotted Bee Balm (Monarda punctata), and Nodding Pink Onion (Allium cernuum), which are adapted to mesic (moderately damp) soils.

The Keith White Prairie is alive with color in the summer and fall and is always a great place to walk. You never know what plants or animals you might see.

Want to feel better? Go For a Walk in the Woods!

Are you trying to decide between working out at the gym and taking a walk in the woods? If you are interested in improving your mental, as well as your physical health, new research recommends heading for the woods.

A quiet path through Mahon Woods in the Cofrin Arboretum on the UW--Green Bay campus.

Most people would probably agree that a walk in the woods (barring mosquitoes) has a reviving effect on our mental well-being. Writers, from Pliny to Thoreau, have touted the recuperative benefits of nature. Frederick Law Olmsted, the Landscape Architect who founded The Clearing, located in Door County, WI, wrote in 1865 “the enjoyment of scenery employs the mind without fatigue and yet exercises it; tranquilizes it and yet enlivens it; and thus, through the influence of the mind over the body, gives the effect of refreshing rest and reinvigoration to the whole system.” In 1985 E. O. Wilson explored this love of nature in his book “Biophilia”. In it he championed the idea that our attraction to nature goes beyond the aesthetic to the genetic, that our love of nature is actually genetically programmed.

A new study led by Richard Mitchell of the Centre for Research on Environment, Society and Health, at Glasgow University agrees with Wilson’s assertion. They looked at the locations that 1800 physically active people chose for exercise and then compared that data to measures of their mental health. Interestingly, only activity in the natural environment was associated with a lower risk of poor mental health. Those that chose to exercise in woodlands or parks had a 50% greater effect on positive mental health compared to those who chose the gym. The study also indicates that the positive effects of activity in a natural area cause a physiological change that goes beyond the effect of positive thought. Our biology actually changes when we experience nature.

There have been a number of theories that have been proposed to try to explain the physiological beneficial influence of nature, but probably the two best-known theories are the Attention Restoration Theory of Kaplan and Kaplan (1989) and the psycho-evolutionary theory developed by Ulrich and his colleagues in the 1990s. These theories explain the influence of nature, especially plants, on the reduction of stress and mental fatigue. Both theories consider the recovery effects of viewing nature to have a biological cause.

Attention restoration theory suggests that fatigue caused by trying to concentrate on a project in the face of continued distractions can be restored by quiet exercise and reflection in a natural environment. It is based on the assumption that natural settings are “quietly fascinating” and draw our attention without our even realizing it. We observe nature in a way that requires no effort, and is pleasing because it creates a sense of order and meaning. However, watching nature is not so attention grabbing that it prevents the reflective thought that allows us to recover from mental fatigue. Natural settings, they argue, also reduce stress because they create a feeling of “getting away” or escaping from the work environment.

Another theory, developed by Ulrich and Parson in the 1990s, argues that our modern world is over-stimulating because it is too visually complex and loud. They argue that natural settings reduce stress because they mimic the natural habitats that we evolved in. We are drawn to and have a positive psychological response to natural settings like woodland edges, grassy meadows and ponds and stream edges. Visiting natural spaces like the Cofrin Arboretum or other natural areas speeds recovery from stress.

Other studies agree with the results reached by Mitchell and his colleagues. Studies by several Japanese researchers have shown that forest walks result in lower blood pressure, pulse rates and cortisol levels, as well as increased heart healthy hormones. A study by Jo Barton and Jules Pretty in 2010 determined that spending just five minutes walking in an outdoor natural setting caused improved mental and emotional health. A study by Roe and Aspinall (2010) found that rural walks had a more restorative effect on mental health than urban walks did. They also found that those with poorer mental health saw even greater restorative effect from walking in a rural landscape. In a different study they found that when children with extreme behavior problems spent time in forest settings, they developed positive emotional responses, like improved trust, over time (Roe and Aspinall 2011).

What is the take home message? Go take a walk in the woods. Nature can help those of us that live and work in complex stressful environments to be physiologically healthier if we take the time to visit natural areas to de-compress. There is a positive biological effect on your body when you experience trees, vegetation, streams and ponds.

Four of UW—Green Bay’s natural areas, The Cofrin Arboretum, Point au Sable, Kingfisher Farm, and Toft Point, provide walking trails. Plan your next walk outside and enjoy the benefits of greater health!


  • Regular exercise in natural environments halves risk of poor mental health:
  • Barton, J.  and Pretty, J. (2010) What is the Best Dose of Nature and Green Exercise for Improving Mental Health? A Multi-Study Analysis. Environ. Sci. Technol., 2010, 44 (10), pp 3947–3955
  • R. Kaplan and S. Kaplan. (1989) The experience of nature: A psychological perspective. New York: Cambridge University Press.
  • Roe, J. and Aspinall, P. (2011): The restorative benefits of walking in urban and rural settings in adults with good and poor mental health, Health & Place 17, 103-113
  • Roe, J. and Aspinall, P. (2011): The emotional affordances of forest settings: an investigation in boys with extreme behavioural problems. Landscape Research.
  • Ulrich, Roger S., Robert F. Simons, Barbara D. Losito, Evelyn Fiorito, Mark A. Miles, and Michael Zelson. 1991. Stress recovery during exposure to natural and urban environments. Journal of Environmental Psychology 11: 201-230.
  • Wilson, Edward O. (1984). Biophilia. Cambridge: Harvard University Press.

Point au Sable Bird Survey: November 3, 2011

Today, Marty Jacobson, Josh Martinez and I conducted bird point counts at Point Sable for sites 3, 5 and 9. Soon after arriving, we had nice looks at a lone Pine Siskin (Spinus pinus) from point 3. When we reached the end of the point, we could see many distant ducks but there was also a Common Loon (Gavia immer) fairly close in (see photo below). Also at the point, we had 9 swans fly over. They were either Tundra (Cygnus columbianus) or Trumpeter (Cygnus buccinators), but we were not sure which. Several other interesting flyovers included 10 Bonaparte’s Gull (Chroicocephalus philadelphia) at point 5, 4 Horned Lark (Eremophila alpestris) from point 6 and a Rusty Blackbird at point 3. Migrant passerines included Fox Sparrow (Passerella iliaca) and Hermit Thrush (Catharus guttatus). Marty asked if Josh or I ever see owls at Point Sable and almost on cue we found two Great Horned Owls (Bubo virginianus). One of the last birds we saw was a Belted Kingfisher (Megaceryle alcyon) fishing in Wequiock Creek.


Common Loon
Common Loon at Point Sable. 3 November, 2011.

Point au Sable Bird Survey: October 26, 2011

Josh Martinez and I conducted point counts at several Point Sable sites this morning. The sky was overcast and the wind speed was around 10 mph. There were quite a few ducks visible from the end of the Point but none were close enough to identify. The most exciting bird of the day was a Horned Grebe (Podiceps auritus) on the bay just off the outlet of Wequiock Creek. We also saw 3 Hermit Thrushes (Catharus guttatus), a Bald Eagle (Haliaeetus leucocephalus) and several species of woodpecker including a very cooperative Downy Woodpecker (Picoides pubescens; see photo). Overall, it was a very quiet morning for birding.


Horned Grebe
Distant Horned Grebe on the bay of Green Bay, October 26, 2011


Downy Woodpecker
Male Downy Woodpecker, Point au Sable, October 26, 2011.


Wind Damage at Toft Point Natural Area

Winds of up to 69 mph swept through Door County on Thursday, September 29th causing extensive damage, especially on the west side of the county. Thousands were without power for two days and Highway 57 between Jacksonport and Baileys Harbor was closed through Saturday. All the state parks located in the county were closed for the weekend.

Toft Point natural area, managed by the Cofrin Center for Biodiversity, is located in Baileys Harbor, WI and was in the path of the windstorm. At least 24 downed or broken trees were counted by the Friends of Toft Point as they inspected the trails on Sunday.

Fallen tree at Toft Point
Toft Friend Charlotte Lukes sits on a fallen tree at Toft Point Natural Area. Photo by Roy Lukes.

Josh Martinez, land steward for the Cofrin Center for Biodiversity will be heading up with UW-Green Bay facilities staff to clear the road and trails at Toft Point on Friday, October 7th. We ask that people remain off the trails and road until after trees can be removed to avoid injury from leaning trees and branches.

Leaning trees
Trees leaning over the trail at Toft Point. Photo by Roy Lukes.

Point au Sable Bird Survey: October 1, 2010 by Erin Gnass

In a short amount of time, undergraduate student, Aaron Groves, and I were able to trek over to Point au Sable and perform just one point count along the shoreline before the downpour of rain began! Upon arriving at the Point, we noticed that the landscape had changed drastically since we had last been there a few months ago. The shoreline was completely covered in the invasive Phragmites australis, making it nearly impossible to view the bay of Green Bay. Regardless, many of the small passerines did not seem to mind this invasive. We found numerous Black-capped Chickadees, Song Sparrows, and one Myrtle (Yellow-rumped) Warbler foraging within the Phragmites and using it for cover. We also observed the following species:  Great Egret, Great Blue Heron, Mallard Duck, Canada Geese, Ring-billed Gull, Red-winged Blackbird, Common Grackle, Ovenbird, Downy Woodpecker, Gray Catbird, White-breasted Nuthatch, American Crow, Blue Jay, and American Robin. Upon hearing the chatter of the Belted Kingfisher and the ever-present European Starling, the rain slowly started to pour, at which point Aaron and I left for the day. We observed a total of 19 species.

Point au Sable Bird Survey: May 17, 2010 by Erin Gnass

With bright sunshine, nearly 60 degrees in temperature, and northerly winds over the weekend, we found many new species and the most total species observed for the season in one morning-a total of 59 species! We observed approximately a dozen Common Goldeneyes performing mating rituals off shore near a few American White Pelicans. A dozen Double-crested Cormorants, Canada Geese, Mallard Ducks, and screeching Caspian Terns passed along shore and overhead through the morning. Spotted Sandpipers and Sandhill Cranes also continue to use the Point. Despite many of the interesting species we observed today, we found a few broken American Robin egg shells, which we have found a few times around the Point. Sadly, the eggs might have blown out of different pair’s nests during some intense wind or rain storms that we have had this April and May.

Of the newest arrivals were Red-eyed Vireos, Yellow-throated Vireos, Least Flycatchers, and Yellow-bellied Flycatchers! While I stumbled upon a Northern Waterthrush out in the open, Aaron spotted our season’s first Black-billed Cuckoo high in an aspen tree, laying fairly still along a branch. We later found it lower in a shrub, perhaps resting after arriving to the Point overnight. And one short of our record of total warbler species observed in one day for the season, we observed 13 total warbler species this morning, including Northern Waterthrush, Tennessee, Golden-winged, Magnolia, American Redstart, Palm, Blackburnian, Yellow, Yellow-rumped, Common Yellowthroat, Black-and-white, Ovenbird, and Nashville Warblers. We continue to observe Warbling Vireos, Rose-breasted Grosbeaks, Swamp Sparrows, Blue-gray Gnatcatchers, House Wrens, Bald Eagles, Baltimore Orioles, Song Sparrows, and many more interesting and magnificent species of birds.

Observers:  Erin Gnass and Aaron Groves (Thank you very much, Aaron, for accompanying and helping me this spring season and best of luck with your Cofrin student research summer field work!)