|
| Astragalus gracilis
Nutt. |
|
| |
| TAXONOMY |
| |
| Family: |
Fabaceae |
| Genus: |
Astragalus |
| |
| Species Synonyms: |
none |
| Common Names: |
slender milkvetch |
| |
| DISTRIBUTION |
| |
| Canada: |
west-central Saskatchewan |
| Saskatchewan: |
west-central Saskatchewan |
| Ecoregion: |
Moist Mixed Grassland |
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| HABITAT |
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| Saskatchewan: |
sandy prairie |
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| RARITY STATUS |
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Provincial
Status According
to Harms (2003): |
Endangered |
| Nature Conservancy
Status: |
G5 S1 |
Saskatchewan
Species at
Risk Status: |
None |
| COSEWIC Status:
|
None |
| |
| Slender milkvetch
is endangered in Saskatchewan because it is extremely rare and highly regionally
restricted in the province. Most local populations are small. Possible threats
have been identified for this species. |
| |
| SPECIES
DESCRIPTION |
| |
| Stems: |
caudex underground, a knobby
crown or proliferating radially; stems few to several, erect, ascending
or creeping, branched, 15 – 80 cm |
| Stipules: |
1 – 4 mm long, lowest
fused |
| Leaves: |
stalk 0 – 3 cm long; leaves
3 – 5 cm long, odd-pinnate; hairs attaching at base |
| Leaflets: |
7 – 21, 5 – 18 mm
long, linear to inversely egg-shaped, tip obtuse to square |
| Inflorescence: |
unbranched, 12 – 40-flowered;
flower stalks ~ 1 mm long; inflorescence stalk axillary and terminal, 4
– 17 cm long |
| Flowers: |
sepal tube 1.5 – 2.5 mm
long, bell-shaped, stiff hairy, hairs white; petals pale to dark purple,
or white with purple keel tip, may dry yellowish; banner 6 – 9 mm
long, strongly upturned; wings 5 – 8 mm long, keel 3.5 – 6 mm
long |
| Fruits: |
pod somewhat reflexed, 4 –
8 mm long, plumply oval or elliptic, fleshy but becoming leathery, filled
with fibrous material when dried; seeds 2.5 – 3.5 mm long, brownish,
smooth |
| |
| ASTRAGALUS
KEY FOR GENERA FOUND IN SASKATCHEWAN |
| |
| 1 Leaves needle-like, distinctly spine-tipped |
A. kentrophyta var. kentrophyta |
| 1 Leaves not needle-like or spine-tipped |
2 |
| |
|
2 Plants without a distinct stem,
< 10 cm tall, densely tufted; flowers often included among leaves
|
3 |
| 2 Plants with a distinct stem, >
10 cm tall, may be erect or creeping, stem not well defined in A. missouriensis;
flowers in distinct inflorescences |
6 |
| |
|
| 3 Leaves simple or with 1 or 2 linear
leaflets |
A. spatulatus |
| 3 Leaves pinnate or with 3 leaflets |
4 |
| |
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| 4 Leaves with 3 leaflets |
A. gilviflorus var. gilviflorus |
| 4 Leaves pinnate |
|
| |
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| 5 Leaf hairs attaching in the middle,
with one side longer than the other; leaflets 4 – 5x as long as wide,
tip acute |
A. lotiflorus |
| 5 Leaf hairs attaching at the base;
leaflets 2x as long as wide, tip rounded |
A. purshii var. purshii |
| |
|
| 6 Leaf hairs attaching in the middle,
with one side longer than the other |
7 |
| 6 Leaf hairs attaching at the base |
9 |
| |
|
| 7 Petals greenish-white or creamy;
plants green |
A. canadensis var. canadensis |
| 7 Petals purplish; plants covered
in greyish or silvery hairs |
8 |
| |
|
| 8 Leaflets in up to 12 pairs; plants
with a definite stem; stipules fused |
A. adsurgens ssp. robustior |
| 8 Leaflets fewer than or equal to
7 pairs; stem not well-defined; stipules not fused |
A. missouriensis var. missouriensis |
| |
|
| 9 Petals yellow, cream or orange,
keel occasionally blue-tinged |
10 |
| 9 Petals blue, pink, or purple |
18 |
| |
|
| 10 Leaves and stems gray-hairy, hairs
1 – 2 mm long, widely spreading |
A. drummondii |
| 10 Hairs of leaves and stem variable
but hairs shorter than 1 mm long |
11 |
| |
|
| 11 Pods hairless or nearly to |
12 |
| 11 Pods distinctly hairy |
15 |
| |
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| 12 Pods sessile or nearly so, stalk
< 1 mm long; pods very fleshy, walls thick, hard and bony when dry |
A. crassicarpus |
| 12 Pods stalked, stalk equal to or
exceeding sepals; pods not fleshy, walls thin |
13 |
| |
|
| 13 Pods linear |
A. racemosus var. racemosus |
| 13 Pods broader |
14 |
| |
|
| 14 Leaflets 2 – 4 cm long; pods
inflated and nearly round in cross section |
A. americanus |
| 14 Leaflets < 2 cm long; pods very
strongly flattened |
A. tenellus |
| |
|
| 15 Flowers small, sepal tube 1.5 –
4.5 mm long, banner 4 – 12.5 mm long |
16 |
| 15 Flowers large, sepal tube >
4.5 mm long, banner > 13 mm long |
17 |
| |
|
| 16 Pods hanging down, stalked |
A. alpinus var. alpinus |
| 16 Pods erect, short-stalked |
A. bodinii |
| |
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| 17 Leaflets without stalks; pods sessile |
A. pectinatus |
| 17 Leaflets with stalks; pods stalked |
A. agrestis |
| |
|
| 18 Pods 1 – 3 cm long |
19 |
| 18 Pods generally less than 1.1 cm
long |
20 |
| |
|
| 19 Pods with two deep grooves on upper
side |
A. bisulcatus |
| 19 Pods lacking two deep grooves |
A. flexuosus var. flexuosus |
| |
|
| 20 Pods spreading to erect |
21 |
| 20 Pods spreading to deflexed |
22 |
| |
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| 21 Flowers small, sepal tube <
4.5 mm long, banner < 13 mm long |
A. bodinii |
| 21 Flowers large, sepal tube >
4.5 mm long, banner > 13 mm long |
A. agrestis |
| |
|
| 22 Pods plump |
A. gracilis |
| 22 Pods strongly flattened laterally |
23 |
| |
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| 23 Inflorescences at most loosely
10-flowered; inflorescence stalks shorter than or only slightly surpassing
leaves |
A. vexilliflexus var. vexilliflexus |
| 23 Inflorescences usually more than
10-flowered; inflorescence stalks longer than leaves |
A. eucosmus |
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