Grade. 

 Date. . 



EXERCISE 21 

 STUDY OF ALFALFA 



Object. To study alfalfa in the field. 



Explanation. It is not expected that all the aims of this field trip can 

 be realized except under very favorable conditions. The number of aims is 

 somewhat large for this reason. It is suggested that the student make rough 

 notes in the field and copy answers into this manual later on page 68. 



Aim 1. To examine the parts of the alfalfa plant and the manner 

 of growth. 



Aim 2. To show when alfalfa should be cut. 



Aim 3. To show the difference between common alfalfa and the varie- 

 gated varieties. 



Aim 4. To show the effect of poor drainage. 



Aim 5. To show the effect of soil acidity. 



Aim 6. To observe whatever diseases, insects and serious weeds may 

 be found. 



Aim 7 To discuss alfalfa culture with an alfalfa grower. 



Aim 1 (a) What is the length of the longest root you find? 



(b) What kind of a root has alfalfa? (See Exercise 5.) 



(c) Draw part of an alfalfa root showing the nodules (Fig. 38). The 

 digging must be careful or the nodules will be shaken off. 



(d) Find the largest alfalfa plant you can. How many stems arise from 

 the crown? 



(e) Early in the season alfalfa may be confused with sweet clover. 

 Draw a leaf of each showing how they may be distinguished. 



Aim 2 (a) -Draw the crown of an alfalfa plant which is ready to cut. 

 Indicate the length of the shoots. 



Aim 3. (a) Dig plants of common and variegated alfalfa. Examine 

 blossoms. How do they differ? 



Aim 4. (a) Find a wet spot in the field of alfalfa. What is the effect 

 on the alfalfa? 



Aim 5. (a) Find a spot (not wet) where alfalfa does not thrive and such 

 weeds are found as sheep sorrel, daisy, paintbrush and plantain. Make a 

 litmus paper test of the soil and subsoil. Describe result. 



Aim 6. Make a list of the alfalfa diseases and insects, also of the weeds 

 found in any quantity. 



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