i have noticed recently a few threads on pests and diseases so i have decided to do up a few pages on some common pests and diseases that are an often occurance so we can refer straigh away to these articles.
so firstly lets take a look at thrips.
thrips is a small slender insect with rasping mouth parts, Most thrips that we notice feed on plant leaves, buds, and flowers of garden and landscape plants. However, a few species are beneficial predators that feed on other insects and mites.
You can recognize thrips using a hand lens or magnifying glass. Adult thrips are slender, and range in size from 1mm to 10mm. juvenielle thrips look a little like a elongated scorpion.
most commonly we will encounter the smaller varieties in bonsai, there are lots of different species that i wont go into as they are all treated accordingly.
Thrips are tiny and tend to feed in buds, within furled leaves, or in other unexposed areas of the plant; their damage is often observed before the thrips can be seen. Numerous black specks of feces scattered over a stippled leaf surface is a clue that damage is caused by thrips, but look for the insects themselves. Lace bugs and other plant bugs also leave black specks.
The thrips life cycle includes the egg, two actively feeding nymphal stages, nonfeeding prepupa and pupa stage, and the adult. Thrips metamorphosis occupies one of those biological gray areas, somewhere between gradual and complete. Thrips have several generations (up to eight or more) a year. The life cycle from egg to adult may be completed in as short a time as 2 weeks during warm weather.
Thrips prefer to feed on rapidly growing tissue. Feeding damage caused by thrips adults or nymphs creates tiny scars on leaves and/or fruit, called stippling. This frequently stunts plant growth and causes misshapen buds. Damaged leaves may also become papery and distorted. Thrips can cause dead spots or blotches to appear on buds, leaves and flowers. infested flowers usually discolor, become pinched or deformed, and often fail to open. Black, varnish-like specks of excrement are a distinguishing feature of thrips activity. Feces may remain on leaves or fruit long after thrips have left. Thrips are poor fliers; damage may first appear in one location then slowly spread over the plant.
so how do we control and iradicate them?
an insecticide will definately do the job but you have to remember the impact of this as it can also kill beneficial insect that are predatory to thrips.
if the infestation is a massive thing i suggest removal by hand, and removal of the leaf to be destroyed then a spray with an insecticide
natrasoap spray is an effective means of controlling the problem.
a pyrethrum + garlic spray is also effective in the iradication and control.
it will most likely take a few applications to kill the life cycle of these nasty little creatures, as they can be quite evasive and their reproduction is quite fast as stated above it can only take about 2 weeks from egg to adult in the right condition and there can be upto or more than 8 generations a year.
these are just a few products that can be used, obviously apply as per instructions on the container. there are other products that are out there aswell i just havent put them in such as the likes of confidor, which can be a bit to harsh for some trees to use on in which way i would be using one of the more natural methods.
i am personally a big believer in keeping a healthy tree means less problems, an unhealthy or stressed tree will attract numerous possible diseases and insects that can cause havoc to our bonsai trees that we invest so much time and effort in, so my best advice is to keep your trees as healthy as possible
please feel free to add anything you like to this, if we can build up a database on this sort of thing it will make an easy referance for anyone who is having troubles with pests and disease.
jamie
taking the top half of trees of since 2005! 
