Lab 6: Crop Growth and Development
Rachel Veenstra 
AGRON 220 Lab: Crop Growth and Development
A worksheet to walk you through the sixth lab session
Task 1: Match each term with the associated crop. Terms may match with more than one crop!
10% bloom
lint
beginning flower
Grain sorghum
loch
beginning maturity
match-head
beginning pod
maturity group
beginning seed
Cotton
micronaire
black layer
milk
blister
milk line
boll
Corn
opposite to alternate leaves
bolting
overwintering
boot
physiological maturity
bracts
Alfalfa
pinhead
candle
pod
CRM
R5.5
dent
Wheat
ray flowers
disk flowers
rosette
dough
silique
ear
Soybean
silk
Feekes scale
solitary flower
first hollow stem
square
full flower
Sunflower
staple
full pod
thumb leaf
full seed
tiller
half bloom
Canola
trifoliate
hard dough
VC
jointing
Task 2: What is the difference between an indicative stage and a descriptive stage?
Provide indicative stages for soybean reproduction.
Provide descriptive stages for corn reproduction.
Task 3: With your group, look up herbicide labels and extension publications, or use the ones provided. Find 8 different crop-stage combinations and fill out the form below as you go. You can use examples from lecture.
Crop
Product/Practice
Indicative Stage
Descriptive Stage
Ex 1
dent corn
silage harvest
R5.5
half milkline
Ex 2
dent corn
DiFlexx Duo herbicide
V10
seventh and tenth leaf
#1
#2
#3
#4
#5
#6
#7
#8
Task 4: To the greenhouse! Using the development posters you are provided (or the links), stage the plants and/or images set out in the teaching greenhouse. Note both the indicative (Ind.) and descriptive stages.
Crop
Ind.
Descriptive Stage
Crop
Ind.
Descriptive Stage
1
14
2
15
3
16
4
17
5
18
6
19
7
20
8
21
9
22
10
23
11
24
12
25
13
26
Task 5: Determine the dry matter in the following samples. Assume you used the microwave method to determine moisture content.
Crop 1: Alfalfa Hay
What is the % moisture of this sample?
Estimated wet biomass: 5 tons per acre
Initial sample weight: 250 grams
Microwave test:
First sample weight: 175 grams
What is the dry matter per acre of this hay crop?
Next sample weight: 130 grams
Next sample weight: 110 grams
Next sample weight: 107 grams
Next sample weight: 103 grams
Final sample weight: 103 grams
Crop 2: Corn silage
What is the % moisture of this sample?
Estimated wet biomass: 15 tons per acre
Initial sample weight: 175 grams
Microwave test:
First sample weight: 132 grams
What is the dry matter per acre of this hay crop?
Next sample weight: 108 grams
Next sample weight: 93 grams
Next sample weight: 81 grams
Next sample weight: 70 grams
Next sample weight: 61 grams
Next sample weight: 52 grams
Final sample weight: 52 grams
Based on the moisture % of this silage sample, is it ready to harvest? What would you estimate the development stage of the corn crop to be?
Other worksheets of Natural science: Plants
