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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 2006

Apr 28 A few Trillium grandiflorum (large white trillium) in flower, UWGB.
Apr 27

New in Flower, UWGB: Prunus nigra (Canadian plum), Ribes cynosbati (eastern prickly gooseberry), Ribes odoratum (golden currant, planted). The forest seems quite dry for this time of year.

Acer platanoides (Norway maple) and Malus sp. ( flowering crabs)) are conspicuously in flower in the City of Green Bay.

Apr 26

Amelanchier arborea (June-berry) in flower in courtyard, UWGB.

New in flower in UWGB's Cofrin Arboretum: Viola pubescens (common blue violet), Ribes rubrum (red currant), Erythronium americanum (yellow trout lily), and a single open flower of Viola pubescens (yellow violet).

This is the first day for the strong characteristic aroma of the opening buds of Populus balsamifera (balsam poplar) in the air of the Cofrin Arboretum (flowering started about April 22).

Apr 25 Viola labradorica (dog violet) and Fraxinus pennsylvanica (green ash) in flower, UWGB.
Apr 24

West Virginia White butterfly observed, Oconto County, Pensaukee (Tom Erdman).

Cabbage Butterfly, UWGB.

Poa annua (annual bluegrass) in flower, UWGB. This species has probably been in flower on some drier, sunny disturbed sites earlier, but this is the first day I have seen it on UWGB.

Apr 22 Acer saccharum (sugar maple) in flower (anthesis) Brown County, UWGB.
Apr 21

First day of flowering for: Anemone quinquefolia (wood anemone), Cardamine diphylla (broad-leaved toothwort), Lamium amplexicaule (henbit), Veronica serpyllifolia (thyme-leaved speedwell).

Arisaema triphyllum (Jack-in-the-pulpit) has fully formed spathes and many people would say they are flowering, although no pollen has been released yet.

Erythronium americanum (yellow trout lily) in flower, Baird Creek Park, City of Green Bay (Kathy Groves).

Gray Tree Frogs calling, Oconto County, Pensaukee (Tom Erdman)

Apr 20

Ribes triste (swamp red currant), Ranunculus hispidus (swamp buttercup), Anemone quinquefolia (wood anemone) in flower, City of Green Bay. Populus tremuloides (quaking aspen) is starting to leaf out conspicuously as the young fruits develop.

First day for Spring Azure butterflies, UWGB's Cofrin Arboretum.

First day for yellow warblers, Brown County (Bob Howe).

First Painted Turtle, crossing the road, UWGB.

Apr 19

Plants first day in flower, UWGB: Cardamine douglassii (purple spring-cress), Cardamine concatenata (cut-leaved toothwort, previously known as Dentaria laciniata), .

Acer platanoides (Norway maple), Betula papyrifera (paper birch), Barbarea vulgaris (yellow rocket), Salix bebbiana (Bebb's willow), Euphorbia cyparissias (cypress spurge) in flower, City of Green Bay.

Apr 18 Erythronium albidum (white trout lily) in flower, City of Green Bay (Amy Wolf). [first day flower uwgb April 20, gf]
Apr 17

Glechoma hederacea (gill-over-the-ground) in flower, UWGB.

Oryzopsis asperifolia (rough-leaved rice grass) in flower (anthesis) Oconto County (Juniper Sundance)

Apr 16 New in flower, UWGB: Carex pedunculata (long-stalk sedge), Salix petiolaris (meadow willow), Salix eriocephala (diamond willow).
Apr 15

Today was the 6th consecutive day of high temperatures in the mid-60's or higher--well above the average high temperatures (low 50's) for this time of year.

Several woody species that produce large volumes of pollen (and therefore some allergic reactions) began to flower today: Acer negundo (box elder), Populus deltoides (cottonwood), Juniperus chinensis (Chinese juniper, but many cultivars and many common names, including the popular "Pfitzer juniper"). If you had a "spring cold" this weekend, you may want to consider the possibility that you have an allergy to one or more of these species. They are all very common and numerous in Green Bay and they are releasing clouds of pollen.

Other species beginning to flower: Carex pensylvanica (Pennsylvania sedge), Sanguinaria canadensis (bloodroot--a few reports as earlyb as 04/12), Caltha palustris (marsh marigold), UWGB.

Elsewhere in Brown County: Shepherdia canadensis (buffalo-berry), Draba verna (spring whitlow-grass) and Erysimum cheiranthoides (worm-seed mustard this one only in cracks in concrete in City GB).

Apr 14

We had several consecutive warm days, and then a little rain yesterday in Green Bay. Today's unseasonably warm temperature (77° F at 4 pm) has promoted a rash of new species in flower on the UWGB campus: Salix humilis (prairie willow), Thlaspi arvense (field pennycress), Veronica perigrina (purslane speedwell) Veronica arvensis (corn speedwell) and Senecio vulgaris (common groundsel).

Abrupt greening of lawns in Green bay area.

Apr 13

Amidst the Yellow-rumped Warblers, Golden-crowned Kinglets, Hermit Thrushes, Song Sparrows, Yellow-bellied Spasuckers, and Brown Creepers at Pt. Sauble, we encountered two new species today for the UW-Green Bay Ornithology class. Two highly vocal Brown Thrashers (first of the year for us) showed themselves plainly to the group during the morning field trip. We also heard a Swamp Sparrow for the first time. Rain tonight probably means a new wave of migrants will be on its way soon (Bob Howe).

Acer rubrum (red maple) in flower (anthesis), UWGB. Some planted Populus deltoides (cottonwood) along East Mason Street are in anthesis today, but not the native plants in natural habitats.

Apr 12

Ulmus americana (American elm), Ulmus pumila (Siberian elm), Thuja occidentalis (white cedar) in flower (anthesis), UW-Green Bay campus. Also Capsella bursa-pastoris (shepherd's-purse) in flower.

Forsythia sp. in flower, City of Green Bay (photograph, to illustrate the species, is from April 30, 2000).

Apr 11

This is the first day that Equisteum arvense (field horsetail) released spores. Also the first day of flower (anthesis) of the earliest Ulmus pumila (Siberian elm) and Populus grandidentata (big-tooth aspen) and the first Taraxacum officinale (dandelions) flowering in sunny south facing slopes adjacent to buildings, UWGB.

This is the first day for suckers (fish) spawning in Mahon Creek, UWGB. Water is so low in the creek that they are finding it difficult to get up the stream.

The forecast for Green Bay today predicts high temperature of about 70 F. We have not experienced a temperature that high since last October. [actual high was 72 F, gf]

Leopard frogs and Toads out (but not yet calling) Oconto County (Tom Erdman).

Apr 09

Our local tree swallows have returned, Town of Cooperstown, Manitowoc County (Joel Trick).

First open flowers on Hepatica acutiloba (sharp-lobed hepatica), Town of Cooperstown, Manitowoc County (Joel Trick). [this plant was long known as Hepatica acutiloba and will appear under that name in many books, but Anemone acutiloba is the currently accepted name, gf]

Red Admiral and Mourning Cloak butterflies and Honey Bees out, Oconto County, Pensaukee (Tom Erdman).

Apr 08

Belted Kingfisher and Northern Flicker have returned in Shawano (Joel Whitehouse).

On 8 April I saw the first phorid flies mating on my compost pile. I hadn't seen any active arthropods on the compost before then, City of Green Bay (Mike Draney).

Big Brown Bats (Eptesius fuscus) are back, Marinette County, Town of Porterfield (Jay Watson).

Apr 07 The weather has turned cold, windy and overcast in the Green Bay area. Rain and even a little snow is predicted for Wisconsin today, but warmer weather is expected to return quickly.
Apr 06 The earliest plants of Salix discolor (pussy willow) are in flower (anthesis of male flowers) on UWGB, although the plant that I monitor on a regular basis has not yet begun to flower.
Apr 05

Yesterdays fire on the west shore of Green Bay was part of a large plan to control the invasive plant Phragmites australis (giant reed). Phragmites has invaded thousands of acres of wetland since 1999, including most of the coastal marshes on Green Bay. It produces dense, nearly pure stands of tall stems that exclude all other wetland plants from the site. For the control effort to have a chance of success, there must be careful followup to kill any surviving plants or they will simply spread back into the cleared areas. Photos and information about Phragmites are provided in the link above.

A few wood frogs calling, UWGB Bayshore Pond (Jenna King). Wood frogs also calling in Keshena (Joel Whitehouse.

This morning we had our first eastern phoebe calling in the yard; in the afternoon, small numbers of wood frogs and spring peepers were calling, and wild leek (Allium tricoccum) has emerged throughout our woods, though still 2 inches or less in height. Town of Cooperstown, Manitowoc County (Joel Trick).

Apr 04

During the afternoon there was a conspicuous smoke plume visible from UWGB, from a fire apparently originating at about the area of the base of Longtail Point/Sensiba Marsh area. The roof in the foreground of the photo is the Weidner Center. I'll amend this entry if I find out more about the circumstances.

The fire above was started by the WIDNR and it was near the base of Longtail Point--confirmed by Heather Gentry who phoned me from the site at about 3:15 pm.

Eastern Garter Snake on the road, Brown County.

Apr 03 Blue-spotted Salamanders reported out, Brown County (Amy Wolf).
Apr 02

This is the first day that I saw a wood chuck out and about, Brown County, Allouez.

Eastern Garter Snake (Thamnophis sirtalis) observed, Oconto County, Abrams area (Juniper Sundance).

Wood ducks at Shawano (Joel Whitehouse.

Apr 01

The earliest plants of Alnus incana (speckled alder), Populus tremuloides (trembling aspen) and Corylus americana (American hazelnut) have begun to flower (anthesis) and many others are very close, Brown County, City of Green Bay.

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Last updated on May 20, 2015