How does your garden grow?
By Eric Danell
How to communicate danger in a pedagogic way
As a university lecturer in mycology I have also had the pleasure of
teaching very young children about mushrooms. I soon realized that some
children did not seem affected by the explanation that a number of mushrooms
are deadly poisonous. Death might be an abstract phenomenon to a young
child, so I had to adapt my pedagogic approach to the experience of my
audience: I explained that if you eat the wrong mushroom, you will suffer
from severe diarrhoea and poo everywhere like a little baby.
That description was enthusiastically accepted by the audience who knew
both poo and babies.
spatella is an indigenous Thai orchid which we grow at Dokmai Garden. (Photo
by Eric Danell)
So, how do we communicate to adults that it is a shame we are currently
destroying the original forests and their creatures, that lost species will
be gone forever, and that new species may need tens of millions of years to
Perhaps we need to change the time scale from the abstract ‘ten million
years’ to ‘how will our descendants, left in a junk yard, judge us 80 years
from now? Then the issue becomes a question of shame and honour.
When I was a child I was warned by my father that a particular knife was
very sharp, and a second later I tried the edge and cut my finger. My father
could not believe his eyes when he saw my ‘stupidity’, and I agree it was
stupid, but on the other hand it is a scientific approach to test a
statement yourself. Many mistakes made by the western countries in 1860-1960
are now repeated by developing countries, in spite of recommendations. The
problem with biodiversity decline is that a band aid will not help if a
species is lost.
The first pedagogic challenge is to explain why we need 1100 wild orchid
species in Thailand, when the shopping malls seem to function fine without
them. We should not use hollow arguments such as ‘all species are equally
important, and society may collapse if we lose one’. Most people can see
that statement is more religious than empirical, and then people may lose
interest in your faith. Better tell the truth: the world becomes poorer,
uglier and less interesting! Replacing an avatar-like forest with rubber
trees and corn is like burning down a national museum to build a chicken
farm. This demands some knowledge in the mind of the discussion partner,
which is why education is extremely important. However, today’s military
regimes in surrounding countries are not educated and since the forests will
be gone in our time the argument of disgusting behaviour will be in vain.
A more clever argument is money. Save the forests to make money on tourists.
Again, it is a matter of education, as most Thais never travel abroad, and
therefore they have only a vague imagination about what eco tourism and
safari is. Proper scientific studies of eco tourism in Australia with actual
dollar signs, in combination with study trips, may do the trick.
I also believe that carbon dioxide as an explanation for the global warming
is wrong, and that this mantra blinds us from real disasters such as the
current extinction of species. Again, education and open discussions between
different scholars (not politicians, not environmentalists, not journalists)
would help people judge for themselves.
If any of our readers have more suggestions on pedagogic approaches to
communicate the importance of supporting conservation efforts, please let us
know on the blog ‘The Last Days of the Orchids’. www.dokmaigarden.co.th.
Is it dangerous to walk barefoot in the garden?
By Eric Danell, Dokmai Garden
Thai: Put on your shoes, or you will get worms!
Farang: What are you talking about??
mollis, a native ebony used to treat worms. If you visit Dokmai Garden you
can see the actual tree. Ketsanee’s grandfather used these fruits regularly
to keep his stomach trimmed.
A foreigner coming to the tropics may not be aware of the
tropical parasites. The background to this conversation is that hookworms
(nematodes in the genera Necator and Ancylostoma) may enter your skin and
cause dermatitis. The worms are actually intestinal, and if present in your
garden they probably originate from dog or cat poo. The dangerous hookworms
are those specialised on man, and they spread via human poo and infect new
victims via the skin of your feet. The hookworms suck blood causing anemia
and may cause severe damage to pregnant women and their babies. The disease
is often symptomless but serious. The worms can migrate everywhere in the
body, and even transfer to newborn babies via the mother’s milk, and kill
the babies. About 10% of the world’s human population is infected.
The worms thrive in moist sandy soils, but will die during droughts and
How do you protect yourself? To avoid the skin rash caused by hookworms from
dogs and cats, give your pets vermicides, and put up a fence so that alien
pets cannot invade your garden. Always wash vegetables from another place
than your own garden. To avoid human hookworms, avoid walking barefoot
outside your garden. If you know that nobody can use your garden as a
toilet, enjoy the grass between your toes!
Since many worm infections occur in the tropics (pinworms, Ascaris affecting
25% of the world’s population, tapeworm and fasciola) many Thais regularly
eat commercial vermicides. Before chemical treatments, the Thais would use
the fruits of Diospyros mollis (Ebenaceae) or the leaves of Azadirachta
indica (Meliaceae). The best vermicide was opium, made from the poppy
Papaver somniferum. www.dokmaigarden.co.th. [email protected]
On slugs and snails
Slugs (no shell) and snails (have shells) may become
pests in a Chiang Mai garden. The Tropical Leatherleaf (Laevicaulis alte
sensu lato, tak nang) is a flat, brown slug which often hides its tentacles.
It is well adapted to the dry lowlands, hiding underground at daytime, and
feeding on your plants at night.
invasive Golden Apple Snail (Pomacea canaliculata, hoi cherry) is an
underwater snail that can grow as large as an apple.
Another Chiang Mai gastropod is the East African Landsnail (Achatina fulica,
hoi tak african). It can grow big as a hand, and has a conical and quite
ornamental striped shell. These snails eat plants and even concrete to get
calcium for their shells. The snail was reported from China in 1931, where
it was introduced as food.
A third invasive gastropod is the Golden Apple Snail (Pomacea canaliculata,
hoi cherry). It is an underwater snail, with yellowish round shells that can
grow big as an apple. Its spectacular pink eggs are laid above the water
level. This snail was introduced from South America to clean fish tanks, and
was promoted as a food for people. It was found in the wild in Thailand in
1984, and is now the most serious pest in rice and taro fields. This has
resulted in an increased use of pesticides. This seems unnecessary, as many
wild fish, birds, mammals and crabs eat the snails. Since such predators are
almost extinct due to cats, dogs and hunting, the snails propagate out of
control. Also in natural wetlands, this snail eradicates the native flora,
and outcompetes its Thai cousin Pila polita (hoi kong), which has white eggs
and darker shells.
All of these gastropods may be vectors of the rat lungworm (Angiostrongylus
cantonensis, pajat toa gom), a nematode that resides in lung arteries of
rats, and may infect humans, causing fatal encephalitis as a result of
undercooked snails or unwashed vegetables. Slugs and snails can be
controlled by fowl, herons and frogs. Nocturnal snail hunters such as
fireflies, which are most spectacular beetles in any garden, benefit from a
heap of branches to promote breeding. Gardeners can make a difference by
creating a refuge for Thai wildlife! www.dokmaigarden.co.th.
Chiangmai Mail Publishing Co. Ltd.
189/22 Moo 5, T. Sansai Noi, A. Sansai, Chiang Mai 50210
Tel. 053 852 557, Fax. 053 014 195
Editor: 087 184 8508
E-mail: [email protected]
Administration: [email protected]
Website & Newsletter Advertising: [email protected]
Copyright © 2004 Chiangmai Mail. All rights reserved.
This material may not be published, broadcast, rewritten, or redistributed.