biodiversity homepage      

Observations by Gary Fewless for Green Bay WI (Lat.N 44.51° Long. W 88.02° ), except as noted. For flowers lacking conspicuous petals or sepals I define "anthesis" as release of pollen by mature anthers.

April 2007

April 30

Trillium grandiflorum (great white trillium) in flower (a few were open yesterday).

Sambucus pubens (red elderberry) in flower

American Toads in full chorus on Prairie Pond, UW-Green Bay's Cofrin Arboretum.

Wild Turkey observed in UW-Green Bay's Cofrin Arboretum (Vicki Medland).

April 29

Green Bay set a new record high temperture for this date, 85° F. The old record was 84° in 1970.

Today is the first day that there is a slight sense of greening in Mahon Woods on the UWGB arboretum.

First day for fully formed inflorescence of Arisaema triphyllum (jack-in-the-pulpit).

Amelanchier laevis (smooth serviceberry; Juneberry) in flower.

Arabis lyrata (lyrate rock-cress), Anemone quinquefolia (wood anemone), Prunus pensylvanica (fire cherry), Carex pensylvanica (Pennsylvania sedge), and Antennaria howellii (pussy-toes) in bloom. Bufo americanus (American Toad) and Hyla versicolor (Gray treefrog) chorusing. Wood ducks observed on Allen Lake. Hartman's Creek State Park, Waupaca County (Tom Nedland).

April 28 First day of flower for Viola sororia (common blue violet), Betula papyrifera (paper birch), Amelanchier arborea (Juneberry, planted tree in the courtyard of MAC Hall, UWGB).
April 27 First day of flower for Anemone quinuefolia (wood anemone).
April 26 Light rain in the early morning and cooler. Temperature of 47° at 10 a.m. in Green Bay.
April 25

A little rain in Green Bay, but most of the day was mild and there was considerable sunshine.

I saw one fully open flower of Viola pubescens (yellow violet) and a few flowering plants of Viola labradorica (dog violet, long known as Viola conspersa), on south-facing slopes.

First day of fully open flowers for Barbarea vulgaris (yellow rocket), City of Green Bay.

This is the first day that I saw Taraxacum officinale (dandelion) in flower away from the buildings and other sources of heat subsidy (those sites had flowering plants 04/15), UWGB.

There was a Great Egret in a stormwater detention pond near the East River, in Allouez.

April 24 Today an abrupt greening of the lawns in Green Bay area was noted. Obviously this happens over a longer period, but today the process reached a critical state of appearance. Several other people also noted the change.
April 23

White-throated Sparrows in our yard in town, City of Green Bay (Vicki Medland).

First day of fully open flowers for Euphorbia cyparissias (cypress spurge) and Cardamine concatenata (cut-leaved toothwort, long known as Dentaria laciniata ), UW-Green Bay.

Green Bay received 0.11 inches of rain today.

April 22

Acer negundo (box elder), Cardamine douglassii (purple spring-cress), Erythronium albidum (white trout lily) Erythronium americanum (yellow trout lily) and Populus deltoides (eastern cottonwood) in flower, UWGB. Also horticultural plants of Acer platanoides (Norway maple) in flower, UWGB.

Widespread flowering of Anemone americana (blunt-leaved Hepatica), Claytonia caroliniana (Carolina spring beauty) in Langlade and Oconto counties.

Hepatica in flower. Eastern Spiny Soft-shell Turtle spotted - Pope Lake. Golden-winged Warblers spotted - pope and marl lakes, Caltha palustris (marsh marigold) in bloom, Hartmans Creek State Park (Tom Nedland).

A good movement of early migrants over the past few days, with White-throated Sparrows, Ruby-crowned Kinglets, Hermit Thrushes and Yellow-rumped Warblers common, Town of Cooperstown, Manitowoc County (Joel Trick).

First American Toads calling, Town of Cooperstown, Manitowoc County (Joel Trick).

I have a relayed report of Great Horned Owl fledglings observed, City of Green Bay, by Bruce Shepard.

April 21

Sanguinaria canadensis (bloodroot) in flower, first day on UWGB campus. I suspect this species was flowering widely today--I saw a small number fully open as far north as Townsend in Oconto County, but only on south slopes and ridge tops, etc. Kate Hutton reported Sanguinaria canadensis in flower in village of Allouez on 04/18

A few Anemone americana (long known as Hepatica americana) and Claytonia caroliniana (spring beauty) in flower, Oconto and Langlade counties.

I "collected" my first wood ticks of the season today in northern Oconto County--just 2 during a long day outdoors.

First day that I smelled the distinctive spring smell of opening buds of Populus balsamifera (balsam poplar).

April 20 First day of flower for Glechoma hederacea (gill-over-the-ground), UWGB.
April 19

A bright, sunny day in Green Bay, temperature 60° F at 1 pm.

Thuja occidentalis (white cedar) and Salix petiolaris (meadow willow) have begun to flower (anthesis), Brown County, City of Green Bay.

Also, Taxus cuspidata (Japanese Yew) and Juniperus chinensis (Chinese juniper) are in flower (anthesis), UWGB; both are horticultural plants.

Lake Sturgeon have begun to spawn in northeasern Wisconsin. I can't check this on a daily basis, so I am not sure when they started.

Smelt (fish) have also been reported entering area streams to spawn. Smelt are said to "run" at this time of year.

April 18

Cloudy, light rain and cool in Green Bay. The temperature at noon was 44° F.

Dirca palustris (leatherwood) in flower, Elton, Langlade County, (Steve Janke).

April 16

First day of flower for Senecio vulgaris (common ragwort), UWGB. Another weedy species of disturbed soils and agricultural fields.

Wood Frogs singing in Menominee County, Wi, Keshena area (Joel Whitehouse).

April 15

A sunny day with high temperature of 55° F in Green Bay

First day of flower for Acer rubrum (red maple), Populus grandidentata (big-tooth aspen) and Taraxacum officinale (dandelion, only a few plants against south-facing walls) on UWGB. Although I suspect it was not the first day of flower, I also saw Capsella bursa-pastoris (shepherd's purse) in flower, UWGB. It is a common weedy species on disturbed sites, but it is not easy to predict where it will appear each year.

First day of flower for Cardamine douglassii (purple spring-cress), Brown County, Village of Allouez.

First Eastern Towhee of the year, Town of Cooperstown, Manitowoc County (Joel Trick).

Erythronium albidum (white trout lily)in flower, wood lots within residential area, City of Green Bay (Amy Wolf).

April 14

This is our first day in the 50's since April 2 and many plants are developing rapidly. Most of the snow from the 11th and 12th is gone, but some snow persists in snow banks and in shaded sites. See the rapid change from April 12 to April 14 on UWGB's Cofrin Arboretum.

First day of flower for Caltha palustris (marsh marigold) on UWGB (just a few flowers). A few early plants of Equisetum avense (common horsetail) plants are dispersing spores.

Suckers (fish) are spawning actively in Mahon Creek.

First Chipping Sparrows of the year today; Fox Sparrows have been common at our feeders for the past week, Town of Cooperstown, Manitowoc County (Joel Trick).

Wood Frog singing, Wilson Lake, Town of Wittenberg, Shawano County (Joel Whitehouse).

April 12

Snow flurries continue into mid-day and Green Bay received an additional 1.5 inches making a total of 4.7 inches for the storm. The aspect outdoors is decidedly not spring-like by most standards. Green Bay has had at least a trace of snow on 7 of the first 12 days of April. Warmer weather is forecast, so the snow will not last long [see photo on April 14]. If temperatures rise into upper 40's and then 50's as predicted, we may see rapid development of many species that have been put on hold by the snow and cold weather.

Some places in southern Wisconsin reported about 8 inches of snow yesterday. Milwaukee had 7 inches of snow before midnight.

April 11

A snowstorm moved into Wisconsin today, with 4-6 inches predicted for Green Bay. Spring is on hold. [Green Bay reported 3.2 inches, for the date, gf]. Last year Green Bay reached a high temperature of 72° F on April 11, today's high was 37°.

April 10

An overnight low of 25° F produced a thin cover of ice on small ponds in the Green Bay area.

Here's a graph of temperatures in Green Bay for the winter of 2006/2007.

April 09 Green Bay received 1.4 inches of snow. There will be little plant development to report until the weather warms up a bit.
April 06

I don't know how they managed it on a day with a high temperature of 30° F, but some Forsythia (Forsythia) plants in the City of Green Bay have begun to flower. The individual that I watch each year is up against a fence (but not against a building). Forsythia is not native here, but is widely planted.

April 05 The early morning low was 21° F in Green Bay and the surface soil is solidly frozen. There is also a firm layer of ice on roadside puddles, etc. Spring developments are more or less on hold until this arctic air mass moves on.
April 04 Light snow in the early morning hours in Green Bay, with just enough accumulation to whiten lawns and some roofs. Periodic flurries were noted all day with a total of 0.3 inches of snow in Green Bay. Areas to the north and west received greater amounts of snow (Rhinelander 2 inches). Winds averaged 24 mph in Green Bay with a peak of 46 mph .
April 01

Salix discolor (pussy willow) has begun to flower (anthesis), City of Green Bay.

First blooming daffodils in the yard - this is nine days earlier than in 2006. These are not close to the house but out in the lawn, City of Green Bay (David Parsons).

© 2001-2004 The Cofrin Center for Biodiversity and the University of Wisconsin Green Bay, All Rights Reserved
Last updated on May 20, 2015