Salix lasiolepis, the arroyo willow, is common in streambeds and on riverbanks below 7000 feet in the western United States. Like the cottonwood, it occurs in wet areas in a wide variety of biomes.
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of the soil a mere three millimeters wide and two millimeters tall!
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Site: UCSC Arboretum
Salix lasiolepis, the arroyo willow, is common in streambeds and on riverbanks below 7000 feet in the western United States. Like the cottonwood, it occurs in wet areas in a wide variety of biomes. |
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Thicks roots with barely-visible hairs. |
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Full zoom on above image, nicely illustrating long root hairs. |
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Deep, thick branched roots. |
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Numerous roots of different sizes. This is clearly a "hot spot" of root activity. |
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Visible through the mud is this thick white root. At this magnification, the root hairs are not visible. |
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Zoom in on above; nice image of root hairs. It is interesting to note that the willow seems to be growing root hairs only where there is muddy soil available; it apparently does not waste energy growing root hairs in the soil's air spaces. |
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Another image of a root utilizing the muddy parts of the soil. |
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Excellent image of extensive root hair development (zoom in on above root). |
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A rotted root. In time, all that will remain here will be an open channel along which water, soil fauna, and future roots will move. |
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This active root seems to have a vague whitish substance surounding it... |
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In this zoom of the above image, you can see that the whitish substance forms a sort of sheath around the root, and is probably due to the presence of soil fungi. The concept of a "rhizosphere", a zone adjacent to roots that is influenced by root activities, is perfectly clear in this image. Soil fungi are presumably feeding on sugars leaking from the root. |
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This image was taken further down the same root. |
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Zoom in on above. |
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This is another image from the same root. |
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Zoom in on above. In an image like this it is impossible to distinguish between root hairs and soil fungi. |
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Three contrasting roots. |
