Download - SEC Area 8 Pathfinders

Author: Alisa Cooper
Grasses
1. What characteristics must a plant have to qualify as a grass?
Grass belongs to the Gramineae (Poaceae) family.
Three major characteristics separate the grass
family from all other plant families:
1. the flowers lack petals and are borne between
bracts in a leafless inflorescence;
2. the leaves are flat, long and slender, and form a
sheath around the stem;
3. the stems are round, generally hollow, and
somewhat swollen at the nodes.
Note: although an unknown plant specimen may
possess one or even two of these characteristics,
that does not necessarily mean you are looking at a grass. It is the combination of all
three characteristics that defines the grass family.
2. What kind of roots do all grasses have?
Monocotyledonous plants (monocots), tend to have fibrous root systems. The growth
and development of these root systems involve production of new roots, root elongation
and branching. A typical fibrous system can be found in the grass family. A fibrous root
system consists of one or several primary roots stemming directly from the seed
(seminal roots), as well as roots developed adventitiously from the lower stem nodes
(adventitious roots, or crown roots). Both seminal and adventitious roots then produce
lateral roots. Subsequently, any of these initial laterals may produce further laterals, and
so on, for few or many further orders of branching.
3. In round numbers, about how many species around the world are there in the grass family called
Gramineae or Poaceae?
There are some 9,000–10,000 or more species of grasses
4. Do the seeds of grasses have two halves as in the bean (a dicotyledon), or does the seed consist of
just one part as in the lily, date, and coconut (monocotyledons)?
Grasses are monocotyledons
5. What unique characteristic in the growth of grass leaves makes it possible for the plant to flourish
even though continually mowed or grazed?
Grass blades grow at the base of the blade and not from elongated stem tips. This low
growth point evolved in response to grazing animals and allows grasses to be grazed or
mown regularly without severe damage to the plant.
Author: Alisa Cooper
6. Name three annual grasses, that is, grasses that sprout from seeds, blossom, bear seeds, then die
the same summer.
Annual Cool Season - Wheat, rye, Annual Bluegrass, and oats; annual Warm Season - corn,
sudangrass, and pearl millet
7. Name three perennial grasses, that is, grasses whose roots live on from year to year although the
top dies down to the crown each autumn.
Perennial Cool Season - orchardgrass, fescue, Kentucky Bluegrass and perennial ryegrass;
perennial Warm Season - big bluestem, indiangrass, bermudagrass, switchgrass, and old
world bluestems.
8. In each of the following cases name a single grass, or more where indicated, from which the
product is made:
a. bread (three grasses)- maize (corn), wheat, rye
b.
brooms- broom grass
c.
fish poles- bamboo
d.
gluten- wheat
e.
grain alcohol (two grasses)-rye, maize (corn)
f.
hay- rye
g.
hominy- maize (corn)
h.
molasses- sugarcane
i.
oatmeal-oat
j.
starch- maize (corn)
k.
sugar- sugarcane, corn
l.
white flour- wheat
9. Learn and discuss about the various uses of grasses by different people around the world.
10. Press, mount, and correctly label the flower stalks or seed stalks of five pestiferous grasses that are
commonly considered to be weeds.
11. In addition to your collection of flower or seed stalks of pestiferous kinds, press, mount, and
correctly name the flower stalks or seed stalks of ten additional grasses that grow in your
neighborhood. This collection may include the plants whose seeds are in your collection of
cultivated grasses.
Resources
1. http://spuds.agron.ksu.edu/Grassint.htm
2.
http://commodities.caes.uga.edu/turfgrass/georgiaturf/WeedMngt/GrassID.pdf
3.
http://mtvernon.wsu.edu/weedscience/publications/Grass99.pdf
4.
http://en.wikipedia.org/wiki/Gramineae
5.
http://www.newworldencyclopedia.org/entry/Grass
6.
http://en.wikipedia.org/wiki/Hominy
7.
http://www.wisegeek.com/what-is-grain-alcohol.htm
8.
http://luirig.altervista.org/photos-int2/f/fishpole_bamboo_phyllostachys_aurea.htm
Author: Alisa Cooper
9.
http://en.wikipedia.org/wiki/Hay
10. http://prescriptiondesk.com/herbal/barley-grass/