Virtual Microscopy
Microscopy Primer
License Info
Image Use
Custom Photos
Partners
Site Info
Contact Us
Publications
Home

Visit Science,
Optics, & You


The Galleries:

Photo Gallery
Silicon Zoo
Pharmaceuticals
Chip Shots
Phytochemicals
DNA Gallery
Microscapes
Vitamins
Amino Acids
Birthstones
Religion Collection
Pesticides
Beershots
Cocktail Collection
Screen Savers
Win Wallpaper
Mac Wallpaper
Movie Gallery

The Black Willow

The Black Willow (Salix nigra) is a hardwood tree that is distributed widely in North America and throughout the eastern United States. These trees grow well in cool soils and temperate climates with their trunks reaching heights up to 40 feet high and having a scaly bark that often becomes very rough. Black willow trees are well known for their ability to assist in preventing erosion, and often naturally keep many river and creek banks from washing away. The sapwood is white, while the heartwood ranges from light brown to pale reddish or grayish brown in color, frequently with darker streaks along the grain.


Cross Section


Radial Section


Tangential Section

A member of the Salicaceae family, which is a very large group of quick-growing deciduous shrubs and trees, black willows are one of about 300 similar species and natural hybrids that have been classified. In fact, there are so many natural and induced variations in this family that exact identification of willows is often difficult even for experts. These trees reside chiefly in the cooler parts of the North Temperate Zone, with a few being found in the Southern Hemisphere.

Willows readily adapt to very wet soils, but also prosper in many dryer regions and are very easy to transplant. In fact, new growths can often be initiated starting from dormant branches (of up to two years growth) simply by projecting the branch into moist soil in the early spring.

Willow trees have long seeds with silky hairs that help in the natural dissemination, especially in their native habitat along watercourses. Black willow wood is used for boxes, crates, woodenware, and novelties. Charcoal resulting from destructive distillation of black willow wood is especially suitable for black-powder manufacture.

Microscopic examination of iron-alum hematoxylin and safranin stained thin sections (see the digital images presented above) reveals a diffuse and porous wood having simple perforation plates and abundant parenchyma. The vessel size is diverse with inter-vessel pits being 6 to 10 micrometers in diameter and orbicular to oval or angular (through crowding) in shape. Libriform fibers are moderately thick-walled and medium to coarse in texture. The rays are unstoried, heterocellular, and uniseriate.

BACK TO THE TREES COLLECTION

Questions or comments? Send us an email.
© 1995-2013 by Michael W. Davidson and The Florida State University. All Rights Reserved. No images, graphics, software, scripts, or applets may be reproduced or used in any manner without permission from the copyright holders. Use of this website means you agree to all of the Legal Terms and Conditions set forth by the owners.
This website is maintained by our
Graphics & Web Programming Team
in collaboration with Optical Microscopy at the
National High Magnetic Field Laboratory.
Last modification: Friday, Aug 01, 2003 at 11:43 AM
Access Count Since February 1, 1999: 36731
Microscopes provided exclusively by: