Botany for civil engineers nene

A civil engineer has to use different building materials including wood.

The quality and durability of the structure depends upon

the wood used.

The life of the structure is also affected by trees grown in

its vicinity.

Hence a civil engineer should have some basic

knowledge about botany.

Presentation by Dr. A.S. Nene

This Presentation is based on an article

Botany of Ancient India

by K.V. Vaze, published in Vedic Magazine Lahore

(November 1922, pages 268 – 282)

K.V.Vaze-Pioneering Author of books and articles on

“Science & Technology of Ancient India

Environment means neighborhood of

Living Things

1. Astrot - things which have no circulation 2. Sastrot - things which have circulation

Sastrot things

I. Arwakstrota (Things having downward circulation)

II. Titakastrota (Things having slant circulation)

III. Utstrota (Things having upward circulation)

Utstrota or plant life

Living Things

Definition of Botany

Indian Botanical Classification

Western Botanists divide trees into two classes viz.;

1) Endogenous or growing from inside and

2) Exogenous or growing from outside.

Ancient Indian Botanists divide trees into four classes viz.;

1. Nissar – Trees having no hard core

2. Antassar- Trees having hard core inside

3. Bahhissar – Trees having hard core outside

4. Sarvassar- Trees having core throughout their cross-section

1.Nissar trees are Pipal, Banyan and Holy fig.

However thick these trees grow they form no core.

Their flowers are closed. Fruits are bunch of flowers

2.Bahhissar trees, Endogenous trees, as per

western Botanist, are Bamboo, Coconut or

Bettle nut and others of this class.

3. Antassar trees or Exogenous trees, as per

western Botanist, are Mango, Jackfruit, Neem

tree and other trees.

4. Sarvassar trees are hard throughout the

cross-section. Tamarind, Babul, Shirish tree

and marking tree are the examples of this

class.

Indian Botanical Classification

Unsuitable trees

Pipal , Banyan , Holy fig, KadambaSaptaparn ,Tamarind Bilva Palash,Pilu ,Kutaj, Shlemantak, Lodhra ,Parijat, Kovider, Shirish, Plaksha,

Mahadroom

Nissar trees and Sarvassar trees are unsuitable construction

Forbidden Trees

• Milky Trees: (with poisonous juices): milk bush

• Thorny Trees: Babul or Prickly pear

• Trees having hard through out: Tamarind or

Bunyan tree.

• Bushes: Which give shelter to small animals and

consequently serpents frequent them.

• Fruit bearing Trees: Mango, Guava etc. People are

tempted to throw stones.

• Other Trees (Trees without hard core)

Forbidden Trees

Unsuitable Trees

Tree Recommended near Habitat

High trees or fruit bearing trees may be

allowed, provided they cast no shadow at

noon or overtop the building. The distance of

tree from house should be twice the height

of tree.

Tree Recommended near Habitat

Trees permitted to grow near Habitat

Confinement of trees (Vratabandha)

Some holy trees may be allowed to grow near buildings, but they should be confined to a certain area within a circular wall. Trees transgressing this boundary by breaking through it, should be pruned to avoid damage to the building.

Classification of Trees

According to Gender

Gender: This subdivisions is based on the

direction of growth of the tree.

• Male trees : Trees strong vertically or in compression

• Female trees: Trees strong laterally or in tension

Male Tree Female Tree

Hard wood Trees

According to Age

Classification of Trees

Age: This subdivisions is based on the five life spans

the tree: Child, Young, Adult, Aged and Dead

The trees in the middle three spans of life are to be used

for constructional purposes. The trees in the extreme two

spans (childhood and decay) of life should not be used.

Directional suitability of Trees

Selection of a Tree for Timber

• in the compound of religious place,

• struck by lightening ,

• scorched by fire,

• grown in covered area, in unhygienic conditions or

• grown along the roadside,

• broken by wind or animals or vehicles impact,

• entangled by other trees or wound by creepers,

• grown in anthills or supporting honey beehive,

• grown on cremation ground or which harbors vultures or

owls.

Do not Select a Tree, which is

To ascertain the stage of life of a tree, a bore through the stem, at two feet above ground is made. The age of the tree is indicated by 1) color of the core,2) hardness and 3) juice oozing from the bore.

If a tree is already cut, instead of juice, the sound produced by tamping with a heavy rod, will indicate the stage of age.

Formation test

Selection of Wood

Knots in Wood

The wood should not be full of or devoid of knots.

For seasoning of wood, it should be placed on sand

with bottom portion facing wind blowing from west or

south direction.

Seasoning of wood

Before felling the tree, the branches of tree should be cut first to avoid unusual strains.

Felling the tree

Preservation of Wood

The wood should be painted to avoid the

losses of oily substance. An oil coat should

be applied every year after rainy season.

Frames and door shutters

Wood for frames and door shutters should be of same

type so that the action of weather may be same on

both. Unequal action produces unequal strains and it

is detrimental to architecture.

Tree Extracts

For seats of balloons extracts of few trees

are specified in Agastsamhita.

The juice of coreless trees contains water retarding

substances (lac) and hence the juice was used in

preparing silk cloth gas holders in ancient India.

Water retarding substances

Conclusions

• The study of botany was very useful and essential

for Indian engineers.

• It had formed a part of ancient Indian Engineering

sciences.

References from Ancient Indian Literature

Agastsamhita Bhrugusamhita Bruhatsamhita Geeta

Kashyapa Shilpa

Manushyalaya

chandrika

Mayamat Panini

Parashariya krushi

Paraskar Gruhyasutra

Rajavallabha Sakaladhikara

Shatapath Bramhana

Shilpadeepak Sukhanand Vastu

Taitariya Bramhana

Vastu Vidya Yogavashishta Yuktikalpataru

For more information contact

Dr. A.S. Nene,

Professor of Civil Engineering (Retd)

V.N.I.T. Nagpur

Email: nene_ashok@yahoo.com