### substance | wood:

Pecan
* also are high in vitamin E and provide extra fiber
  - contain the toxin juglone that can cause laminitis in horses
  - exist in the river bottomlands of Texas and northern Mexico
  - require at least two varieties to insure cross-pollination
* are a good source of protein and fiber and are rich in potassium and phosphorus
  - multimillion-dollar industry
  - popular food item eaten in their natural form or as a component in other food dishes
  - true southern belle
  - unique tree species
  - very close relative
* are also a good snacking nut
  - major ingredient in praline candy
  - prone to infection by fungi, especially in humid conditions
  - an excellent source of monounsaturated fatty acid - similar to olive oil
  - another native American nut
  - common across the state
  - currently the only major native nut-producing tree in North America
  - dormant
  - edible fruit
  - long lasting and, when stored properly, hold their freshness for up to two years
* are native to North America where they are cultivated today
  - floodplains and river-bottoms, and have an inherently high water requirement
  - nut trees
  - nuts
* are one of the largest fruit-bearing trees
  - oldest crops and are native to Texas
  - top cash crops of north Louisiana
  - part of pecans
  - plants
  - pollinated by the wind
  - rich in protein, potassium, zinc, vitamin E, magnesium, carbohydrates, and folic acid
* are the fattiest nut
  - only tree nut that is truly native to the United States
* can be part of a balanced and varied diet
  - become an important health food becasue of their high level of monounsaturated fats
  - help lower total blood cholesterol and combat heart disease
  - last up to six months in their shells if refrigerated
  - replace walnuts
* contain oil that compares very favorably with oil from other oil seed crops.
* continue to mature.
* have a much thinner shell, making it easier to access the meat or kernel of the nut
  - strong tendency toward alternate-year bearing while in the wild, unmanaged state
  - slight bud swell and some leaves showing
  - their origins in prehistory
* last a long time, particularly when frozen, and can hold their freshness for up to two years.
* lower low-density lipoprotein cholesterol in people with normal lipid levels.
* thrive in soil that is damp and wet.

### substance | wood | pecan:

Shelled pecan
* absorb odors and turn rancid quickly.
* can keep six months in the freezer.

### substance | wood:

Petrified wood
* Some petrified wood is considered a semi-precious stone.
* common example of permineralization.
* is Washington's official state gem
  - actually rock formed by the gradual replacement of wood by minerals
* is an example of a permineralized fossil
  - wood that has been permineralized by silica
  - official symbol of Alberta, Washington, Mississippi, and Arizona
  - better yet and often imitates rotting wood
* is formed by both processes over a long period of time
  - when a mineral called silica is deposited in pores of dead tree trunk
  - fossilized wood and can also be polished, or left as is
  - found across the continent and around the world
  - one of the few fossil remains found in the rocks at the foot of the cliffs
  - the official state fossil
* occurs as a cast of soft, whitish silica.

Poon
* are trees
* is wood