Tiny springtails under the microscope
The days of using general slug pellets are nearly over. An
announcement from DEFRA has banned metaldehyde slug pellets from Spring
2020. They say "metaldehyde poses
an unacceptable risk to birds and mammals." The pellets being taken off the shelves contain
metaldehyde or methiocarb. Don’t worry though, you won’t be needing to get the
flashlight out to go into the garden at midnight on a slug hunt. There will be
alternatives that claim to be less toxic to the environment. Some shops are
stocking the new products now.
The new pellets are ferric phosphate based and are
classified as suitable for use by the organic grower. They contain ferric
phosphate or iron III phosphate, which affects the calcium metabolism in the
gut system of snails and slugs causing them to stop feeding and die within
three to six days.
Although the ferric phosphate is less toxic than
metaldehyde, there remains the problem of the other ingredients in the tablets
- known as chelators. These chemicals help bond the iron molecules and make
them more toxic to the molluscs. Unfortunately they also affect earthworms,
and, if consumed in large quantities, can poison pets.
There are other products coming to market such as the wool
pellets but I have yet to see or hear anything positive about them. The
compressed wool deters the slugs only until it gets wet, then the slugs crawl
all over them so they are probably more effective in drier climates. They do
work better than eggshells or coffee grounds though but at the moment are very
expensive. Back to pellets then.
Courgettes
Our corgettes are finally doing something. For weeks now
they have just sat there looking sorry for themselves but now have sprung into
life with wild, reckless abandon. I think they have been using all of their
energy to form roots ready for the growth spurt. We did have a couple of male flowers
initially which don’t produce the courgette and these probably come about to
help pollinate the female flowers and entice insects such as bees who will
return to the plants once the female flowers are produced.
You can make use of some of these male flowers by
deep-frying them, though make sure you leave enough on the plant to ensure
successful pollination. You'll know when your plants have started to produce
female flowers, because female flowers have an immature courgette fruit behind
them, while the male flowers are produced on long, thin stalks with no such
swelling.
Courgette Tip
The trick to avoiding a glut of courgettes is to pick them
while they are still small - anything up to about 20cm (8in) - and to pick them
regularly. Picking and eating some of the male flowers will also help to slow
production.
Springtails
The damp conditions have been a perfect breeding ground for
springtails. You might have never seen one of these six legged creatures
because they are only a couple of millimetres in size.
Springtails (Collembola) can be prolific with 100,000
reputed to live in each cubic metre of top soil. Most have a tail-like
appendage folded up under their abdomen called a furcula which is held under
tension. If they feel threatened it can be released to catapult them into the
air to escape. They don’t seem to care where they spring to when disturbed and
can spring anywhere.
They live in soil and in leaf litter where they eat mainly
decaying plant material, fungi and bacteria. Some species are believed to feed
on algae, pollen and insect faeces.
I have found the small creatures (that are not classified as
insects but ‘Entognatha’) mainly in small plug cells where moisture and algae
can sit making them perfect environments for them. When I repot or pack plant plugs
I give them a few sharp taps on a hard surface and the springtails fall out and
scuttle away.
When numbers reach outbreak levels springtails may be found
indoors on floors and around windows. Ponds are occasionally covered with a
fine scum made up of millions of tiny springtails floating on the water
surface.
Control
Springtails aren’t usually an issue but they can take over
your houseplant soil if it is wet and they do make you feel like scratching
when you see them. They usually die off quickly when the soil dries out without
the need for any chemicals.
