GHf12 lab 1 complete - drcrow.orgdrcrow.org/_f2012/GHf12/GHf12 labs/GHf12 lab 1 complete.pdf · 2012-10-16 · As a ﬁrst step, we will begin by selecting lab team members to work

General HorticultureLaboratory 1 - fall 2012

John H. Crow, Ph.D.

© 2012 John H. Crow, Ph.D., all rights reserved

Plant Form and DiversityGeneral Information

The objective of this laboratory is to begin to discover and explore the forms and variations of plants. The study of the plant form is plant morphology, and when we are talking about the form without need of a microscope we are talking about gross morphology. Anatomy is a part of morphology, but we will not take up anatomy in this lab. When you admire plants at home or elsewhere, you are seeing the overall gross morphology of the plant, but that form is closely linked to its anatomy, so we will need some understanding of that down the line too.

Horticulture is centered on beauty and garden crops. The fact that science forms a substantial part of the basis for both is the reason that you come out of this course with a new level of appreciation and understanding, not only of horticulture, but of science too. In each lab, we will learn something something useful. It is not my intention to burned you with meaningless exercises with content that you will forget 15 minutes after leaving the building.

Drawings and Observations

You will be expected to make drawings on plain paper with a pencil! It will be your responsibility to bring both to class. Some of you may be talented and will be able to make gorgeous reproductions of what you are observing, but some of you may not be able to draw a straight line. Do not despair, it does not matter. I will help each of you do what is actually required to learn. In addition, I do not wish to deprive any of you of technology and will allow digital photography. This means you can use your phones and digital cameras in lab. There is a catch however, you will still need to sketch what you see in lab. You will then produce the photos neatly on paper and draw over the photos or produce a neat drawing with the aid of your photos. Don’t worry, I will demonstrate. Believe me you can really learn and have fun with this, but it will take some work and concentration. Like anything worthwhile in your life, you will get out in proportion to what you put in.

By the way, I will have a few digital tools in class with me. Using these tools, we will be able to share our observations, questions, and thoughts in real time.

I have provided a set of minimum terms that correspond with features you will be able to observe and draw or otherwise characterize.

Please refer to the class website at http://www.drcrow.org for information about lab, lecture requirements, and grading. Understand that you have to participate in laboratory and perform well each and every week. If you cannot commit to this, drop the course now.

General Horticulture - Laboratory 1! Page 2


http://www.drcrow.org

http://www.drcrow.org

Preparation

Before you begin each lab, make sure that you have white, unlined paper on which you can draw, make graphs, etc. You must get a lab kit at New Jersey Books or the Rutgers Book Store that will help you do dissections, make slides, etc. I recommend getting a magnifying glass (hand lens); it will be very useful to you and, if you call yourself a biologist, you should have a good one (I recommend the Bausch & Lomb 10X Hastings Triplet hand lens at about $33.00 and it will last a lifetime). As a rule, I will have mine with me.

As a first step, we will begin by selecting lab team members to work with. This proves to be more efficient when doing repetitive tasks and is a means to teach and test each other. Two or three of you should make up a group. Report the group member names to your lab instructor and give the group a name or letter identifier ("A” Students Group, for example). This group will work together the entire semester and sit next to each other in lab.

In this laboratory we are going to examine the features of a number of plants that are provided. Some of the plants come from the campus and others come from the Rutgers greenhouse or elsewhere (my home, for example). You will also find a number of the illustrations provided in this set of laboratory materials that I hope will be useful.



General Instructions

Where appropriate, examine the plant materials and try to sketch what you see. This does not require artistic talent but some patience and good observational skills. Use magnification where appropriate. If you do employ magnification make sure that you know the relative size of what you are looking at and where the magnified view is located. If you do this, you will better understand the plant and what you will be seeing. Remember, you can use digital!

In this lab I will want you to be able to label plant parts accurately, so, if in doubt, ask me to assist you or check your work.

Plants tend to have clear sets of patterns. If you learn these patterns, you will much more easily recognize what you are looking at and appreciate the variation and beauty of nature. Professor Crow will help you with these and the laboratory will give you a chance to observe the patterns in living, preserved, diagrammatic, and photo representations of plant materials.

Not only does the external morphology of the plant have clear patterns, but the anatomy of the plant is also important and is supremely rich in diagnostic patterns you can easily learn. Looking inside a plant will require some patience and a little skill but you will master it quickly if you care to. When we do this, you will see how exciting the relationship is with respect to the beauty you see.

Go from big to small. Look at the whole plant. Examine closely details with a hand lens. Later, we will look even more closely. For example, when you look at a leaf, examine the overall look of the leaf, get closer and examine the vein patterns, leaf margins, and hairs with a hand lens or available dissecting scope (this is a glorified hand lens) I would look at some small, but interesting, details such as hairs.

Do not get bogged down making excruciating drawings. Prof. Crow will have run through the 'rules' or methodology at the beginning of this lab. We will continue to learn how to do this in order to increase your speed, skills, and powers of observation. Maintain a record with your camera anytime you wish.

Biology is the science of living things! Botany is known as the beautiful science and horticulture dwells on this fact, so take your time and enjoy the labs.



Cone and Fruit MorphologyThe seed plants Angiosperms) all have seeds, as you might expect, and all have structures that surround the seeds. Sometimes the covering is for protection, dispersal of the seed, and so forth. In the Gymnosperms we usually have something a bit different from what we might think of as fruits found in the Angiosperms but there are still similarities and if one is generous with the definition of “fruit” then we can see that the fruit is really just a covering for the seeds.

On the following page are some common “fruits.” It is easy to recognize these for what they are but at least one example might fool you at first. More on that one later. Here, the Gymnosperm examples have recognizable cones and the two brown objects on the left are seen as such. The large one is from a Ponderosa Pine and the smaller one is from a Giant Sequoia, the largest living plants. Both were collected in Sequoia National Park.

How the cones are different from the true fruits is illustrated by the remaining 5 true fruits? The answer is, by the way, the number one distinguishing feature separating Angiosperms and Gymnosperms. The Angiosperm fruits illustrated are tomato, banana, corn, apple, and a peach. Where are the seeds found in all of these examples (including the cones)?

How about the ear of corn? Identify the fruit and identify the seed or seeds. Explain.

Later in the semester we will study fruits in more detail but there is no reason to get off to a slow start with respect to the basics. At that time we will carefully refine the uses of the scientific terms and our concepts. We will see how liberties are taken by botanists with some of the most basic terms and fruit types and how laymen use and misuse these words too.

How would you define fruit?

What is a seed?

Can you think of any other type of Gynmosperm “fruit” or do they all have cones?

Do any plants, other than Angiosperms and Gymnosperms, have seeds and “fruits?” If not how do they reproduce? How about ferns?





Shoot MorphologyThe Superfical, External Parts of a Plant

Some of the photos provided are examples of the terms. If I were you, I would label the photos too. Make sketches of everything you observe and remember that you can use digital.

Sketch an entire plant. For the moment we are going to emphasize Angiosperm plants.

Label: shoot and root, stem, nodes, internodes, terminal bud(s), axillary buds, leaves, stipules, petiole, and blade (lamina). What is a leaf called if it has no petiole?

Are the roots as regular as the stems in terms of brancing patterns? What are some significant differences between roots and stems.

Describe the types of leaves and arrangement using terms discussed in lecture.

Arrangement of leaves: alternate, opposite, decussate, and whorled.

Leaves: simple vs. compound

Compound leaves: pinnate, palmate, and trifoliate are basic. We also have bipinnate, tripinnate, and so forth.

Now, look at the venation of leaves. We see several types: pinnate, palmate, parallel, and open. “Open” or dichotomous applies only to one seed plant. Which one?

Look closely at the leaves and see how the small nets are formed in all but the dichotomous venation. Can you find any places where gases may enter and leave the plant (you will have better luck on the underside).

Some simple leaves are lobed. Can you suggest some names for a few of these? Leaves also have shapes that are variously named. For example, chordate, lanceolate, ovate, etc. The tips and bases are also named but we will not dwell on that here.

The margins of leaves vary greatly and have particular names. A few are: entire, dentate, serrate, serrulate, crenate, and so forth. Identify a few margins from the plants before you.

Angiosperms are divided into two main groups, the Monocots and the Dicots. How are these different. If I were to hand you a plant, could you tell me which I gave you?

Can you see any hairs? On stems? On roots? On roots?



For the plant to the right, what is the leaf arrangement?

How would you describe the leaf?

Is there a petiole?

Monocot or Dicot?

Describe and label what you see to the right.

Can you tell if this is a Monocot or Dicot?

For the plant to the right, describe the leaf arrangement.

Describe the venation pattern.

Monocot or Dicot?

Describe the venation pattern here.

Monocot or Dicot?

Describe the margin.

Describe this leaf or leaves. Is it simple or compound?

How about the venation pattern? What is the margin like?

Monocot or Dicot?



Terms for Familiarization with the plant body

Compare lots of plants and make sketches – look at ferns and other sorts of plants too. This list is meant to be a guide for your observations.

Shoot! Stem

LeavesLamina (blade)PetioleStipules

Sessile leaves

Roots! Tap! Reticulate

! ! *Compare shoots with roots

Leaf arrangementAlternateOppositeDecussateWhorled

VenationPinnatePalmateParallelOpen

Observe the smaller venation patterns

LeavesSimpleCompound

Pinnate! Once, bipinnate, tripinnate, etc.PalmateTrifoliate

LobedPinnatePalmate



Shape! Ovate

LanceolateChordateHastateEtc.

MarginsSmooth (entire)Serrate

SerrulateCrenateDentateetc.

Woody vsHerbaceous

Bark

Angiosperms vsGymnosperms

ConifersEtc.

MonocotsDicots

Flowering Plants vsCryptogams

Succulent

TreesShrubs

AnnualsPerennials

HardwoodsSoftwoods



Other kinds of plantsFernsCycads (are Gymnosperms ... why?)BryophytesLycopods

Make additional notes and lists below



Documents

GHf12 lab 1 complete - drcrow.orgdrcrow.org/_f2012/GHf12/GHf12 labs/GHf12 lab 1 complete.pdf · 2012-10-16 · As a ﬁrst step, we will begin by selecting lab team members to work