Thrips or Spider Mites? How to tell the difference
The signs of thrips and spider mites are very similar, making it pretty difficult to see the difference between Thrips and spider mites.
Thankfully they are some ways to identify whether you’re dealing with Spider mites or Thrips.
Telling the difference between Spider mites and Thrips can be a little tricky at first. Since they both feed on the chlorophyll present in the leaves, they leave small white spots on them which is generally why they are confused.
Apart from that similarity they actually have nothing to do with one another, they’re not even in the same family! Thrips are insects and spider mites are part of the Arachnid family.
Here’s what we’re going to cover:
What are the difference between Thrips and Spider Mites?
The main difference within the symptoms of spider mites is the way the white (or grayish) marks appear. With mites the white marks appear mainly along the main-rib and veins of the leaves whereas with Thrips it will be randomly distributed.
This is due to the fact that the mites live under the leaf and the thrips move around (or fly around) on the top of the leaves.
Let’s get into the differences in detail:
Impact of Mites and Thrips on your plants
Thrips | Spider Mites | |
|---|---|---|
| Visible differences |
|
|
| Location on the leaves | Above the leaves. Once Thrips are big enough by looking close enough you will be able to see them crawling around. | Below the leaves – Spider mites live under, lay eggs and die under the leaves. It’s very hard to see individual mites but by looking under the leaf you can notice the black dots. |
| Webbing | No. | Yes – Webbing will appear under the leaf at first. Once the colony is well developed it will spread to the buds. Here’s a step by step evolution |
| Infestation method | When they can fly they will do so from one part of the room to the next. If they are not able to fly than they will crawl from leaf to leaf or by going down one plant and up to then next. | From leaf to leaf or by crawling down the plant and up the next. |
| Flight possibility | Sometimes – Depending on the specie thrips are able to live. Generally the one’s that invade Marijuana cultures have the ability to fly. This is the main reason why you’ll notice random spreading making you think “how the hell did they get there”. | No – Spider mites being a part of the Arachnid family they cannot fly. |
| Egg location | Thrips lay their eggs within the soft tissue of the plant. This isn’t damaging to the plant itself but protects the eggs. | Mites lay their eggs within the webbing under the leaves or across the bugs, depending on the size of the colony |
| Hatching period | 2 to 7 days, depending on the specie | 3 to 5 days, depending on the specie |
| Lifespand | Up to 45 days | Most species live between 14 and 21 days |
| Size | Between 0.5 mm and 1.5 mm | Under 1.0 mm |
What are the similarities between Thrips and Spider Mites?
Thrips and Spider mites actually have a couple things in common, whether it’s where they feed or the environment they live in.
Let’s get into it:
Similarities between Mites and Thrips
| Similarities | Spider Mites and Thrips |
|---|---|
| Environment | They both enjoy hot and dry environment. Over 25°C (77°F) and under 30% Humidity. |
| Feeding | Spider mites and Thrips feed on the chlorophyll within the leaves of the plant. That is the reason why you can see the white spots |
| Hibernation phases | Thrips born in late summer will go into diapause until spring time where the specie can thrive again. Spider mites eggs on their end can stay in hibernation mode for months until they are waken up. |
| Treatment methods | As long as your spider mite colony hasn’t developed an immunity, all mainstream organic or chemical pesticides are effective on both (ex: neem oil). |
Spider Mites or Thrips – Which is worst?
If you’ve been following up on our grow journal you’re aware that we’ve been battling an infestation; At first we thought it was spider mites but now we’re positive it’s Thrips (How to tell the difference? Here’s our guide).
The signs of both these little suckers are actually extremely similar, showing small white marks on your leaves, some more impacted than others. Luckily the actions to get rid of both are pretty much the same, but we’ve covered all that in our guide linked above.
So to recap:
Comparison between Spider Mites and Thrips
| Spider mites | Thrips | |
|---|---|---|
| Easy to kill | No – Depending on the type they can develop resistances, making them so hard to kill | Yes – A repeated treatment will do the trick |
| Immunity | Yes – Very strong capability to develop resistance to any treatment. To know more about spider mites check out our in depth guide | No – Thrips are not known to immunize themselves. |
| Visible by the naked eye | Barely – Since they live under the leaves and measure between 0.5 mm and 1 mm they are very hard to see | A little easier – You can spot them moving around above the leaf or flying around. They get up to 1.5 mm and white or black depending on the stage of life making them easier to see. |
| Resistance to treatment | Strong – Spider mites are know to be very resistant to most organic or chemical treatments. On top of that as we said further up they will develop an immunity very quickly. | Low – Thrips will die on the first time you spray them. This issue lies with the eggs, that’s why it is important to respray every 3 day at least 3 times. |
| Threat level to marijuana | Very High – Spider mites are one (if not the) of the most feared Marijuana Pests and for good reason. They eat away the chlorophyll of the leaves | Medium/High – The direct danger to the plant is actually about the same since Thrips attack and finish by killing you leaves. Furthermore once they’ve developed enough they actually fly around from plant to plant.What really reduces their danger is the fact that you can treat the infestation fairly easily. Remember to spray every 3 day at least 3 time after the first application. |
| Speed of spreading | High – In optimal conditions and without and treatment in a month there can be over 800 000 individuals! Prevention and Early Action is key. | Medium/High – Once thrips have matured and are able to fly they will invade you grow space quickly. Once they’ve hatched in the soil they will develop themselves on that plant. Once they’re |
With that we’ll let you make you mind, but honestly with experience on both, much rather thrips than spidermites (although thrips can be a head ache also)
Alright folks that’s it for this one ! Hope it was useful and you now are able to spot the differences between both pests
Until next time, be safe and grow easy
