Natural History and You - The President's Forum
by Dave Wagner


Watching Flowers Bloom for the First Time in Spring


It is not often that I see the goldthread, Coptis laciniata, in bloom. Saturday, March 8, I led a group of botanists along the lower Brice Creek Trail in the Cottage Grove District, Umpqua National Forest. There were many patches of Coptis just coming into bloom. It is a treat to see so many of these delicate flowers. Seeing these at the beginning of their bloom period made me think about others I've seen already this spring.

Our usual first bloom was early this year; in town I saw both spring beauty (Cardamine nuttallii) and Indian plum (Oemleria cerasiformis) fully in bloom on the last day of January. Normal date for both of these around Eugene has traditionally been February 15. That average date has, however, gradually been moving up thanks to global warming.

There was a landmark article in the 2 January issue of Nature (one of the most prestigious international science journals) that suggested there is, thanks to global warming, a significant mean advancement of spring events by 2.3 days per decade. The conclusions reported there involved comparative analyses of studies of over 1,700 species. There was a second note in the same issue that examined variation in change based on latitude; this note suggested that at our latitude the shift is closer to 4.2 days earlier per decade. This means that since I started making observations of first bloom in spring of 1977, the average first bloom times can now be expected to be from about five to ten days earlier.
David Wagner

FLOWERING SEQUENCE OF NATIVE SPECIES, ALTON BAKER PARK, EUGENE
2nd edition, March 9, 2003
by David Wagner, for the Eugene Natural History Society

The following plants were observed during the first years of the UO Herbarium spring plant walks. The number at left refers to the week of the walk, with 1.00 denoting the first week of March, and 9.00 denoting the ninth week after the first week in March (= sometime in late April). 3.60 for the blood currant means that average time of first bloom for Ribes sanguineum was between the third and fourth week of March. The number of years each was observed is also given. These results are from the first twelve years of the walks, 1977-1988; the number in the column on the right shows how many of those twelve years the plant in question was observed.

MARCH
1.00 Alnus rhombifolia white alder 3
1.00 Cardamine oligosperma western little bittercress 12
1.17 Cardamine nuttallii spring beauty 12
1.17 Oemleria cerasiformis osoberry, Indian plum 12
1.17 Populus trichocarpa black cottonwood 12
1.42 Draba verna spring whitlowgrass 12
1.73 Berberis aquifolium Oregon grape 11
2.57 Salix sitchensis Sitka willow 7
3.33 Alnus rubra red alder 6
3.58 Nemophila parviflora small-flower grovelover 12
3.60 Ribes sanguineum blood currant 5
3.83 Acer macrophyllum bigleaf maple 12
4.00 Erythronium oregonum fawn lily 1
4.00 Ranunculus occidentalis western buttercup 1
5.17 Ribes divaricatum straggly gooseberry 6
5.18 Rubus ursinus Pacific dewberry 11
5.33 Claytonia perfoliata common miner's lettuce 12
APRIL
5.50 Dicentra formosa bleeding heart 12
5.58 Maianthemum racemosum big smilacina 12
5.83 Tellima grandiflora fringecup 12
5.89 Calandrinia ciliata redmaids 9
6.00 Carex aquatilis water sedge 1
6.00 Salix lucida lasiandra Pacific willow 1
6.18 Lupinus micranthus field lupine 11
6.33 Delphinium trolliifolium tall larkspur 12
6.50 Amelanchier alnifolia serviceberry 6
6.50 Mertensia platyphylla western bluebell 12
6.50 Maianthemum stellatum little smilacina 10
6.67 Claytonia linearis aquatic claytonia 3
6.67 Claytonia parviflora small flowered claytonia 9
6.70 Fraxinus latifolia Oregon ash 10
6.73 Lithophragma parviflora prairie star 11
6.75 Ceanothus cuneatus common buckbrush 12
6.75 Claytonia sibirica Siberian miner's lettuce 12
6.83 Barbarea orthoceras American wintercress 6
6.83 Triphysaria pusilla dwarf owl-clover 6
7.00 Quercus garryana Oregon white oak 6
7.09 Cornus nuttallii Pacific dogwood 11
7.25 Marah oregana bigroot, wild cucumber 12
7.58 Acer circinatum vine maple 12
7.67 Matricaria discoidea pineapple weed 12
7.83 Carex deweyana Dewey's sedge 6
8.00 Hydrophyllum tenuipes Pacific waterleaf 6
8.00 Ranunculus uncinatus disappointing buttercup 2
8.36 Crataegus suksdorfii Suksdorf's hawthorn 11
8.38 Tolmiea menziesii pig-a-back plant 8
8.50 Carex obnupta slough sedge 6
8.55 Sanicula crassicaulis pacific sanicle 11
9.00 Carex arcta northern clustered sedge 1
9.00 Luzula campestris field woodrush 2
9.08 Galium aparine bedstraw 12
9.18 Eschscholzia californica California poppy 11
9.33 Thalictrum polycarpum tall western meadowrue 12
MAY
9.50 Lupinus rivularis riverbank lupine 10
9.64 Prunus virginiana chokecherry 11
10.00 Alchemilla occidentalis western lady's mantle 2
10.90 Rosa nutkana Nootka rose 10
11.20 Carex stipata sawbeak sedge 5
11.22 Cornus stolonifera redstem dogwood 9
11.38 Poa pratensis Kentucky bluegrass 8
11.71 Vicia americana American vetch 7
11.75 Heracleum lanatum cow parship 12
11.75 Oxalis suksdorfii western yellow wood-sorrel 12
11.83 Toxicodendron diversilobum poison oak 12
11.86 Bromus sitchensis Sitka brome 7
12.09 Symphoricarpos albus common snowberry 11
12.25 Physocarpus capitatus ninebark 12
12.33 Rubus parviflorus thimbleberry 3
12.42 Urtica dioica stinging nettle 12
12.50 Melica subulata onion grass 2
12.80 Danthonia californica California oatgrass 5
13.00 Dichelostemma congesta cluster-lily 1
13.00 Juncus articulatus jointed rush 1
13.00 Potamogeton crispus curly pondweed 1
13.00 Rumix salicifolius willow dock 6
JUNE
13.50 Juncus bufonius toad rush 6
13.50 Myosotis laxa small-flower forget-me-not 2
13.75 Juncus effusus common rush 4
14.00 Glyceria elata tall mannagrass 1
14.00 Satureja douglasii yerba Buena 2
14.00 Veronica americana water speedwell 1
14.17 Elymus canadensis Canadian ryegrass 6
14.33 Ranunculus aquatilis white water buttercup 3
14.50 Philadelphus lewisii Pacific mock-orange 6
14.75 Achillea milllefolium yarrow 4
15.00 Festuca rubra red fescue 1
15.00 Gnaphalium palustre lowland cudweed 1
16.00 Oenanthe sarmentosa water-parsley 2


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