PLANTS AND PEOPLE- Botany 328- Laboratory
LABORATORY 9: Wood and Paper
INTRODUCTION:
The goal of this laboratory is to familiarize you with the natural phenomena of wood, its basic
anatomy, properties, and uses. By the end of this laboratory you should be able to recognize the basic
components of a tree trunk both at the macroscopic and microscopic levels. You should be able to
differentiate between gymnosperms and angiosperms on the basis of wood anatomy. Additionally,
because wood is of major importance in the world economy and the global ecosystem in general, you
should be able to recognize the numerous products that owe their existence to the natural production of
wood.
One of the most important products which comes from wood is paper. We are all aware of the
importance which paper holds in our daily existence. However, we are often caught in our unaware
when it comes to realizing the simple steps that go into the process of making paper. So, today we will
work through the simple steps which go into making paper. The ultimate result will be homemade paper.
ACTIVITY:
Numerous items relating to wood are on display in the laboratory. You will find samples
related to wood anatomy and general structures. You will also find samples which will enable you to
compare the wood anatomy and structure of different species. Take some time to carefully observe
these samples.
Other samples on display are the products made from wood. Carefully observe and compare
these samples. Note the numerous types of paper products.
Break into groups of four and follow through with the steps for making sheets of homemade
paper. Take note of the process which yields paper. Record and be familiar with the steps involved in
paper-making.
WOOD:
1. Examine the wood XRT cuts on display. Draw an example of one XRT cut labeling each side and the
brief characteristics of each.
2. Examine the wood XRT cut on display. Where is the heartwood? Where is the sapwood? What is
the difference between the two?
3. Examine the wood cross section displayed. What was the age of this tree when it was cut? Why do
the growth rings occur in such an amazing pattern of alternating rings? Note the horizontal rays. What
purpose do these rays serve?
4. This is Pinus, an example of a gymnosperm. Note the sticky resin. Name 2 products which are
derived from resin. What purpose does the resin serve in the overall life of the pine tree?
5. Examine the microscopic thin sections (XRT). Note the resin canals and homogeneity of xylem cell
types. What type of conducting cells make up the xylem in this case? Is this an angiosperm or
gymnosperm?
6. Examine the microscopic thin sections (XRT) of the slides provided. Note the two types of xylem cell
types. What do we call each of these cell types? Is this a monocot or dicot? Gymnosperm or
angiosperm? Do you see resin canals?
7. Examine the herbarium specimens provided. These are examples of some important temperate trees.
Make note of the family and genus for each, as well as the common name. Also, list a few characters for
each which allow you to differentiate between them.
8. Note the XRT section. Is this a monocot or dicot? How are the vascular tissues arranged? This is
bamboo.
9. Note the bracket fungus which infested this wood. The fungal hyphae grow throughout the vascular
tissues of the tree and eventually give rise to the fruiting structure you see here.
10. This is balsa wood. Notice that it is floating on water. What does this tell you about the density of
the wood?
11. Note the lignum vitae mallet. Notice that it does not float, but actually sinks in water. What does
this tell you about the density of this wood?
12. Note the bark on display. What is bark? What are the components of bark?
13. Note the different wood blocks. Using the hand lens provided, examine the blocks paying special
attention to the xylem cells and other features which are exhibited. Look for rays in oak blocks. Why do
we refer to Gymnosperms as softwood and Angiosperms as hardwood?
WOOD PRODUCTS:
1. Examine the wood products on display. Make a list of the products which are provided in class. You
are now more aware of the products which come from wood.
2. Tear a piece of paper and using a microscope, examine the torn ends. What do you see?
3. In groups of four, make paper and record the steps you took.