


Plants
in a acre 

Plants
in a hectare 

Area of acre & hectare 

Measuring
small lots 

Water 

Measuring
inch of water 

Measures
& weights of water 

Measuring area 

Computation
of acreage 

Measures
of heat 

Standard
multipliers 

Cubic feet 

Metric
system 

Convert
multiplications 

Measuring
equalents 

Fertilisers – NPK 

NPK – availability 

Oil
cakes – NPK 

Conversion
factors 

Soil rating chart 

Element
deficiency 

To
find the number of plants required to plant an in acre, multiply the
distance apart that the plants are to be set in the rows, by the distance
between the rows, then divide 43,560 (the number of square feet to the
acre) by the result.
Example
– suppose the plants are to be set 2 feet apart in the rows and
the rows are 2 feet apart. 2 x 2 = 4 feet, 43,560 divided by 4 =10890,
the number of plants required to the acre.
If the plants are to be set one inch apart, it would be necessary to
multiply 43,560 square feet by 144, the number of square inches in a
foot, giving 6,272,640 plants required to the acre if set out one inch
apart. If set 2 inches by 2 inches apart, multiply 2 x 2=4 inches, and
divined 6,272,640 by result 4, which equals 1,568,160.


Distance
in feet 
Plant
Density 
Distance
in feet 
Plant
Density 
1x1 
43,560 
12x12 
302 
1x1.5 
29,040 
12x15 
242 
1.5x1.5 
19,360 
12x16 
226 
2x2 
10,890 
15x15 
193 
2x2.5 
8,712 
16x16 
170 
2x3 
7,260 
15x18 
161 
2.5x2.5 
6,969 
15x20 
145 
3x3 
4840 
16x20 
136 
3x4 
3,630 
18x18 
134 
4x4 
2,720 
18x20 
121 
4x4.5 
2,420 
18x21 
115 
4x5 
2,178 
20x20 
108 
4.5x4.5 
2,151 
18x24 
100 
5x5 
1,742 
21x21 
98 
5x6 
1,452 
24x24 
75 
6x6 
1,210 
25x25 
69 
6x7.5 
960 


6x8 
907 
27x30 
53 
7.5x7.5 
774 
27x27 
59 
8x8 
680 
28x30 
51 
7.5x9 
644 


8x10 
544 
30x30 
48 
9x9 
537 
30x36 
40 
10x10 
435 
33x33 
40 
9x12 
403 
36x36 
33 
10x12 
363 
40x40 
27 


10, 010 Sq. mts. 
Distance
in Mts. 
Plant
Density 
Distance
in Mts. 
Plant
Density 
1x1 
10,010 
4.5x4.5 
494 
1x1.5 
6,673 
5x5 
400 
1.5x1.5 
4,448 
5x6 
333 
2x2 
2,500 
6x6 
278 
2x2.5 
2,000 
6x7.5 
222 
2x3 
1,668 
6x8 
208 
2.5x2.5 
1,600 
7.5x7.5 
178 
3x3 
1,112 
8x8 
156 
3x4 
834 
7.5x9 
148 
4x4 
625 
8x10 
125 
4x4.5 
556 
9x9 
123 
4x5 
500 
10x10 
100 



S.No 
Unit 
One
Acre 
One
Hectare 

Area 
0.404
Hectare 
2.471
Acre 
1 
Sq. Feet 
43,560 
1,07,636 
2 
Sq. Yards 
4840 
11,959 
3 
Sq. Mtrs 
4051 
10,010 
4 
Sq. Inches 
62,72,640 
1,54,99,584 
5 
Grounds 
18.15 
45 
6 
Cents 
100 
247.13 
7 
Guntas 
40 
98.840 
8 
Ares 
40.48 
100 



10 rods x 16 rods … 
1
acre 
8 rods x 20 rods… 
1
acre 
5 rods x 32 rods… 
1
acre 
4 rods x 40 rods… 
1
acre 
5 yds. X 968 yds… 
1
acre 
10 yds. X 484 yds… 
1
acre 
20 yds. X 242 yds… 
1
acre 
40 yds. X 121 yds… 
1
acre 
208 7/10 feet x 208 7/10 feet… 
1
acre 
220 feet x 198 feet… 
1
acre 
110 feet x 396 feet… 
1
acre 
60 feet x 726 feet… 
1
acre 
120 feet x 363 feet… 
1
acre 
20 feet x 2178 feet… 
1
acre 
30 feet x 1452 feet… 
1
acre 
25 feet x 1742 feet… 
1
acre 
200 feet x 108.9 feet… 
½
acre 
147 ½ feet x 147 feet… 
½
acre 
100 feet x 145.2 feet… 
1/3
acre 
120 ½ feet x 120 ½ feet… 
1/3
acre 
100 feet x 108.9 feet… 
¼
acre 
104 3/8 feet x 104 3/8 feet… 
¼
acre 
73 ¾ feet x 73 ¾ feet… 
1/8
acre 



By volume 
Hydrogen
2 
By
weight 
Hydrogen
1 
Oxygen
1 
Oxygen
8 


Maximum
density at 4° Cent.
Between 4° Cent. and 0° Cent., water expands by cold 

(An
inch of rain) 
Water is
measured by the acreinch, which means sufficient water to cover one
acre, one inch deep. For instance, six acre inches is water sufficient
to cover six acres one inch deep, tow acres three inches deep or one
acre six inches deep.
One acre contains 43,560 square feet or 6,272,640 square inches.
An inch deep of rain on an acre yields 6,272,640 cubic inches of water,
which, at 277.274 cubic inches to the gallon, makes 22,622.5 gallons;
and as a gallon of distilled water weights 10lbs., the rainfall on an
acre is 226,225 lbs. Avoirdupois. At 2,00 lbs. To
the ton, an inch deep of rain weighs 113.115 tons per acre, or for every
100^{th} of an inch (1 cent.) considerably over aton of
water falls per acre. 


Cubic
inches 
Lbs.
Weight. 
Kilogrammes. 
Litres. 
Gallons 
One
lb. Weight … 
27.73 
1 
0.454 
0.454 
0.1 
One
gallon … 
277.3 
10 
4.54 
4.54 
1. 
One
Cubic foot … 
1728. 
62.3 
28.31 
28.31 
6.23 
One
Cubic Yard … 
… 
1682.7 
764.5 
764.5 
168.27 
One
Ton (weight) … 
… 
2240. 
1016. 
1016. 
224. 
One
Barrel … 
… 
360. 
163.3 
163.3 
36. 
One
Hogshead … 
… 
540. 
244.9 
244.9 
54. 



Where
a field or piece of land is not a regular area, such as a square or
a rectangle, the simplest method of calculating its area in square feet
or yards, is to draw a sketch showing the measurements of each side
(taking care to draw accurate angles), and then divided the sketch into
convenient triangles. Calculate the area of each triangle and
add; the total thus arrived at will be the area of the irregular land.
The area of a triangle can be found by multiplying the base by onehalf
the altitude, altitude meaning the perpendicular line drawn from the
vertex of the triangle to the corresponding base. 

In
the computation of acreage the easiest method will be links.
7.92inches = 1 link. 
100
links, or 66 ft., or 4 poles = 1 chain 
10
chains long by 1 broad, or 10 square chains = 1 acre, or
100,000
square links = 1 acre 
80
chains = 1 mile. 
To
reduce square links to acres, point off five figures to the rights,
that is, divided by 100,000, the result is acres and a fraction in decimals.
Multiply the decimals by 4 and points off five places again, which gives
rood and a fraction in decimals. Multiply the decimal by 40 and
mark off 5 figures, then we get poles
E.g.,
1234567 square links 
=12.34567
acres 
=
.34567 x 4 
=1.38268
roods 
=
.38268 x 40 
=15.30720
poles 
Answers
– 12 acres, 1 road, 15.30720 poles. 


Three scales
are in common use, Fahrenheit (F.), Centigrade (C.), and Reaumur (R.).
The freezing and boiling points of water on each of these scales are:

Freezing. 
Boiling. 
Fahrenheit … 
32° 
0° 
Centigrade … 
212° 
100° 
Reaumur
… 
0° 
80° 
To
convent F. to C. subtract 32, multiply by 5 and divide by
9.
To convent C. to F. multiply by 9, divide by 5 and add 32.
To convent F. to R. subtract 32, multiply by 4 and divide
by 9. 

Circle, area

=
Square of radius x 3.14159 
Circle circumference

=
diameter x 3.14159, or 31/7 nearly 
Circle circumference

=
radius x 6.283185 
Circle diameter

=
circumference x 0.31831 
Circle diameter

=
Square root of area x 1.12838 
Circle radius

=
Circumference x 0.159155 
Circle radius

=
Square root of area x 0.56419 
Circle side of sq. of eq. area 
=Diameter
x 0.886 
Circle side of inscribed square 
=Diameter
x 0.707 
Cone or Pyramid, solidity

=
Area of base x onethird of altitude 
Ellipse, area

=
Product of diameter x 0.7854 
The area of the surface of 
=
Square of the diameter x 3.1416
sphere 
The volume of a sphere

=
Cube of the diameter x .5236 


How
to calculate the cubic content of a tree (Measuring
round timber.)
The
conventional method of finding the cubic contents of round timber is
as follow: 
Multiply onefourth
of the average girth square by the length;
Or G2 X
L/4
Note:
 if
the girth is taken in inches and the length in feet, divide the result
by 144 to obtain the contents in cubic feet. 

1 Metre (m)

=10 decimetres=39.37 inches.
=100 Centimetres (cm.)
=1000 Millimetres (mm.) 
10 Metres 
=1
decametre=10.93611yds. 
100 Metres 
=1
hectometre=109.3611 yds. 
1000Metres 
=1
kilometre =1093.611 yds 
10 Millimetres (mm) 
=1
Centimetre (cm)=0.3937 inch. 
10 Centimetre 
=1
decimetre=3.9371 inches. 
5 cm (Centimetre) 
=
About 2 inches. 
Kilometre
is 0.621 of a mile, or 1093.6 yards or about 3/8 of a mile. 
Litre
is 61 cub. Ins, or 1.76 imperial pints, or 0.22 of a gallon. 
Gram
is 15.432 grains Troy. 
Kilogram
is approximately 2.205 pounds avoir. (2 lbs. 3 ozs.) 
I yard 
=
.914401 metres. 
I mile 
=
1.609347 kilometres 


To
convert 
Multiply by 
Cubic
centigrade into fluid ounces
… 
0.0352 
Litres
into fluid ounces
… 
35.2 
Fluid
ounces into cubic centimetres
…

28.42 
Pints
into litres …

0.568 
Grams
into grains …

15.432 
Gram
into ounces avoir …

0.03587 
Grams
into ounces troy …

0.3215 
Kilogrammes into pounds …

2.2046 
Grains
into grams …

0.0648 
Ounces
avoirdupois into grams … 
28.35 
Ounces
troy into grams …

31.104 
Metres
into inches …

39.37 
Inches
into metres …

0.0254 


1 Teaspoon 
5 ml. Or 5 gms 
1 Level tablespoonful 
3 level teaspoonfuls 
1 fluid Ounce 
2 table spoonful 
1 Cupful 
8 fluid ounces 
1 Pint2cupfuls 
16 fluid ounces 
1 Quart2Pints 
32 fluid ounces 
1 Gallon4Quarts 
128 fluid ounces 
1 Millilitre 
1 cubic centimetre 
1 Litre1000 millilitres 
1.057 liquid quart 
1 Percent10, 000 parts per million 
8 fluid ounces 100 gals 
1 Pound avoirdupois 
453.59 grams 


S.No. 
Fertiliser 
Available
% 
N 
P 
K 
1 
Ammonium Sulphate 
21 
 
 
2 
Calcium Ammonium Nitrate 
25 
 
 
3 
Urea 
46 
 
 
4 
Single Super Phosphate 
 
16 
 
5 
Triple Super Phosphate 
 
48 
 
6 
Sulphate of Potash 
 
 
4850 
7 
Murate of Potash 
 
 
5160 
8 
Bone Meal 
3.5
 4.5 
24
 25 
 
9 
Di Ammonium Sulphate 
18 
46 
 
10 
UreaAmmonium Phosphate/Potash 
14 
35 
14 
11 
UreaAmmonium Phosphate/Potash 
14 
28 
14 
12 
UreaAmmonium Phosphate/Potash 
22 
22 
11 
13 
UreaAmmonium Phosphate 
 
28 
28 
14 
Ammonium Nitro PhosphateGrade1 
18 
18 
9 
15 
Ammonium Nitro PhosphateGrade2 
15 
15 
15 
16 
Rock Phosphate 
 
25 
 
17 
Ammonium Nitro Phosphate (Sulphate) 
20 
20 
15 


S.No. 
NITROGEN
Fertilisers 
% 
S.No. 
PHOSPHATE
Fertilisers 
% 
1 
Urea 
46 
22 
Di ammonium phosphate 
53 
2 
Liquid ammonia 
82 
23 
Basic clog 
14 
3 
Ammonium Nitrate 
33 

POTASH
Fertilisers 

4 
Ammonium sulphate 
20.5 
24 
Potassium chloride 
60 
5 
Ammonium chloride 
25 
25 
Potassium sulphate 
50 
6 
Ammonium carbonate 
24 
26 
Potassium Magnesium sulphate 
28 
7 
Ammonium bicarbonate 
17 
27 
Kynite 
19 
8 
Ammonium sulphate nitrate 
26 
28 
Potassium carbonate 
66 
9 
Calcium nitrate 
15 
29 
Potassium nitrate 
44 
10 
Calcium ammonium nitrate 
20 
30 
Sylvinyte 
20 
11 
Calcium Cyanamid 
21 
31 
Corpalite 
17 
12 
Ammonium sodium sulphate 
16 
32 
Copper sulphate 
2535 
13 
Aqua ammonia 
20 
33 
Copper carbonate 
57 
14 
Ammonium Phosphate 
20 
34 
Zinc Sulphate 
2325 
15 
Sodium Nitrate 
16 
35 
Magnesium Sulphate 
910 

PHOSPHATE
Fertlisers 

36 
Magnesium carbonate 
4 
16 
Rock phosphate 
25 

IRON
Fertilisers 

17 
Single Super Phosphate 
16 
37 
Ferrous sulphate 
20 
18 
Double Super Phosphate 
32 
38 
Calcium sulphate 
23 
19 
Triple Super Phosphate 
48 
39 
Calcium oxide 
55 
20 
Ammophos 
48 
40 
Calcium carbonate 
32 
21 
Bone meal 
20 





Material 
Percentage composition
N
P2O5 K2O 

Castor cake 
4.04.4 
1.9 
1.4 

Groundnut cake 
6.57.5 
1.3
1.5 


Cottonseed cake
Decorticated
Undecorticated 


1.6
1.6 

6.9
3.6 
3.1
2.5 

Rape cake 
4.8 
2.0 
1.3 

Linseed cake 
4.7 
11.7 
1.3 

Coconut cake 
3.4 
1.5 
2.0 

Palmnut cake 
2.6 
1.1 
0.5 

Neem or margosa cake 
5.25.6 
1.1 
1.5 

Safflower
cake
Decorticated
Undecorticated 
7.9
4.9 
2.2
1.4 
1.9
1.2 

Sesamum cake 
4.76.2 
2.1 
1.3 

Mahua cake 
2.5 
0.8 
1.9 

Jambo cake 
5.0 
1.7 
1.9 

Karanj cake 
4.0 
0.9 
1.3 

Niger cake 
4.7 
1.8 
1.3 



Elements 
Multiplied
by 
Gives
corresponding
quantity
of 
Nitrogen 
4.854 
Ammonium sulphate 
Nitrogen 
2.222 
Urea 
Nitrogen 
3.846 
Ammonium sulphate
nitrate 
Nitrogen 
4.000 
Ammonium chloride 
Nitrogen 
3.030 
Ammonium nitrate 
Phosphoric acid (P2O5) 
6.250 
Super phosphate, single 
Phosphoric acid (P2O5) 
2.222 
Super phosphate, double 
Phosphoric acid (P2O5) 
2.857 
Di calcium phosphate 
Phosphoric acid (P2O5) 
5.000 
Bonemeal, raw 
Potash (K2O) 
1.666 
Muriate of potash 
Potash (K2O) 
2.000 
Sulphate of potash 
Ammonium sulphate 
0.206 
Nitrogen 
Sodium nitrate 
0.155 
Nitrogen 
Urea 
0.450 
Nitrogen 
Ammonium sulphate
nitrate 
0.260 
Nitrogen 
Ammonium chloride 
0.250 
Nitrogen 
Ammonium nitrate 
0.330 
Nitrogen 
Super phosphate, single 
0.160 
Phosphoric acid (P2O5) 
Super phosphate, double 
0.450 
Phosphoric acid (P2O5) 
Di calcium phosphate 
0.350 
Phosphoric acid (P2O5) 
Bonemeal, raw 
0.200 
Phosphoric acid (P2O5) 
Muriate of potash 
0.600 
Potash (K2O) 
Sulphate of potash 
0.500 
Potash (K2O) 


SL
Sandy Loam
SCL Sandy Clay Loam
CL Clay

S.No 
Type 
Light
Soils  SL, SCL 
Heavy
Soils  CL 
1 
Acidic 
0
– 5.9 
0
– 5.0 
2 
Neutral 
6
– 7.5 
6
– 7.5 
3 
Weekly Alkaline 
7.6 – 8.0 
7.6 – 8.0 
4 
Moderately Alkaline 
8.1  8.5 
8.1 – 9.0 
5 
Highly Alkaline 
8.5 and above 
9.1 and above 

S.No. 
Nutrient 
Low 
Medium 
High 
1 
Organic carbon (as a measure of available nitrogen) OR 
Below 0.5% 
0.50.75 % 
Above 0.75% 
2 
Available Nitrogen (N) Natrajani 
Below 280kg/ha 
280560kg/ha 
Above 560kg/ha 
3 
Available
Phosphorus (P) Bhaswaram – P2O5 
Below 8kg/acre 
8kg20kg/acre 
Above 20kg/acre 
4 
Available Potassium (K)
Potash
– K2O 
Below 60kg/acre 
61kg – 120kg/acre 
Above 120kg/acre 
S.No 
SL 
SCL 
Cl 

1 
0
– 1.0 
0
– 1.5 
0
– 2.0 
Normal 
2 
1.1 – 2.0 
1.6 – 3.0 
2.1 – 4.0 
Critical for Germination 
3 
2.1 – 3.0 
3.1 – 4.5 
4.1 – 6.0 
Critical for growth 
4 
Above 3.0 
Above 4.6 
Above 6.0 
Injurious to most crops 


Severe deficiencies of individual essential elements
produce a set of characteristic effects in the external appearance of
leaves, stems, roots, blossoms and fruits. Visual symptoms of nutritional
deficiency include stunted growth, chlorosis, mottling of leaves, abnormal
curling of leaves, leaf discolouration, necrosis, premature senescence
of leaves and blossoms. The following is an account of visual symptoms
of deficiency of individual essential elements. 
When
plants are deficient in nitrogen they become stunted and yellow in appearance.
This yellowing usually appears first on the lower leaves, the upper leaves
remaining green. The matur4e parts of the plant are first affected
because nitrogen is translocated from the older to the younger actively
growing regions. Flowering is reduced. 
Deficiency symptoms of sulphur resemble those of nitrogen deficiencies.
However, unlike nitrogen, sulphur does not appear to be easily translocated.
The leaves are light green to yellow, appearing first along the veins
of the young leaves. The stems are slender. 
Particularly
in cereals, the shortage of phosphorus will cause marked reduction in
plant growth. Young plants are stunted under severe deficiency of
phosphorus. Dark green or bluegreen foliage is one of the first
symptoms of phosphorus deficiency in many species. Often, anthocyanins
develop along the veins. Fruits ripen slowly. 
The
deficiency symptoms usually appear first on the lower leaves of annual
plants and progress towards the top. The leaves are dark bluegreen
to pale green with marginal chlorosis and under necrosis appearing first
on old leaves. Growth is subnormal and under severe conditions,
terminal and lateral buds may die. Potassium deficiency is associated
with a decrease in resistance to pests and diseases.

Magnesium
deficiency symptoms first appear on the lower leaves and in many species
of plants it results in interveinal chlorosis of the leaf in which only
the veins remain green. Severely affected leaves may wilt and
shed or abscise without the wilting stage. Brittleness of the
leaves is common and necrosis often occurs.

The
deficiency of calcium stops the development of terminal bud; plant growth
ceases in the absence of adequate supply of calcium. Leaves are
chlorotic, rolled and curled. Plants fail to develop due to failure
of terminal buds. Roots are poorly developed and they are prone
to infection by bacteria and fungi. In corn, deficiency of calcium
prevents the emergence and unfolding of the new leaves.

A deficiency of iron appears on the young
leaves of plants. It is most frequently seen in crops growing
on calcarious or alkaline soils. Many crops exhibiting deficiency
of this element are blue berries, sorghum, soyabeans, straw berries,
vegetable crops and ornamentals. The young leaves develop an interveinal
chlorosis which progresses rapidly over the entire leaf. In severe
cases the leaves turn completely white. Interveinal chlorosis
appearing first on young leaves is the most striking symptoms of iron
deficiency. All aerial parts become chlorotic and often necrotic.
The leaves may be completely bleached, the margins and the tips are
scorched.

The leaves often show an interveinal chlorosis,
with veins green and leaf web tissue yellow or white, appearing first
on young leaves. This mottled chlorosis may spread to the old
leaves. The stems are yellowish green which are often hard and
woody. Carotenes are reduced. Plans are badly stunted in
severe cases of deficiency.

Deficiency of zinc was observed in corn,
sorghum, rice, cotton, vegetables, legumes, and citrus. Zinc deficiency
leads to “little leaf” and ‘rosette’ in fruit trees. Leaves are
chlorotic and necrotic, sometimes with premature shedding of leaves.
Flowering and fruiting are much reduced under conditions of severe zinc
deficiency.

Copper deficiency was retorted on crops growing
on peat and muck soils. Wilting of terminal shoots takes place,
frequently by death. The leaf colour is often faded due to the reduction
of carotene and other pigments. Flowering and fruiting are curtailed.
Copper deficiency causes iron accumulation in the nodes of corn plants. 
Interveinal chlorosis and mottled appearance
are the major symptoms with molybdenum deficiency. Leaf blades
become necrotic and disintegrate, leaving only a much reduced strip
along the midrib resulting in the symptom known as ‘whiptail’.

Deficiency of Boron is reported in citrus
fruit. Terminal leaves are necrotic and shed prematurely.
Tissues of plants with this deficiency appear hard, dry and brittle.
Roots are short and stubby. Plants are dwarfed and stunted.
Flowering and seed production are severally affected, or lacking.
In citrus, the peel is uneven in thickness, the fruit is lumpy, and
gummy deposits can be seen on the fruit.

In the heat of the day, the tips of the
young leaves wilt and dangle down, Wilting is followed by chlorosis,
bronzing and necrosis. Under severe conditions of deficiency,
plants are spindly and stuned.
