Any questions about pesticides?

[Sweetestdew]

My friend family makes mao feng and she is open about the fact they use pesticides.
Right now I am having a conversation about pesticides with her, are there any questions you guys would like me to ask her about pesticide use?
Im using this as a chance to better understand why and how pesticides are used.

[pedant]

cool! i have some for her:

which pests are typical? which pests are not so bad, and which are the worst ones?
guessing it depends on the growing region.

how do you know which pesticide(s) to use? do you select based on an actual pest you're dealing with?

do you apply pesticides prophylactically, or do you apply them on-demand when a problem presents itself?

how do you determine applicate rates and timing? do you just go by the product's label? are they specifically labeled for tea plants?
do you apply them with the intention of hopefully meeting meeting some residue limit criteria (for export or otherwise), or do you not really care?

thank you

[.m.]

This is very interesting topic. I think pedant had already formulated above most of the questions i have. Here's a few more addressed to anybody knowledgeable about these things:
- What are decomposition times of the pesticides used now vs. in the past? And how big is the residue present in the processed tea?
- How many different pesticides are used?
For example, from what I've heard (correct me if i'm wrong) the importation rules to EU have a very strict limit to the residue of each pesticide, but not an overall limit for the sum. Sometimes i wonder how can all the plantation teabag tea be imported, when small importers of whole-leaf tea often struggle with shipments seized due to unexpected residue findings.
- How long do the pesticide stay in the plant and the soil? I've heard a story of a tea made in a garden that was reportedly completely pesticide free for a couple of years, but the tea still didn't pass a limit for the residue.

[d.manuk]

Did you grow tea naturally in the past, and if yes why did you make the switch to pesticides?
If you grew tea naturally in the past, did you notice a flavor difference after the change?

[aet]

What pests. are used in their plantations?
How they applied ?
When they are applied?
What is the approx. elevation of their plantations?
Which exactly bugs are troubling them ? ( we have entomologist in team who can solve the problem ) .
Do they hold any certificates despite using the pesticides? ( like green food , CN organic ...etc.)
Can she provide full chem test report ? ( pest being check and amount being found ...mg/1kg )

[Sweetestdew]

A few months ago I asked for questions about pesticides for a convesation I was going to have with my friend who was open about her family's pesticide use.
Here is our conversation.

There were some translation issues and it ended a little early because I didnt want to bother her, but I think there are good insights.


https://thesweetestdew.com/2019/10/22/a ... esticides/

[pedant]

thanks for sharing the conversation. it ended just when it was getting good though!

i wanted to hear about which pests her uncle sprays for

[Baisao]

I am curious about what specific pesticides are used (by brand or chemical).

I have smelled beta-cyfluthrin (or its carrier agent) on some teas from Taiwan. It’s a nice sweet smell— like floral five spice— so I can see how it goes with teas but for someone like me who used to apply it, it’s an unmistakable smell.

[Baisao]

- What are decomposition times of the pesticides used now vs. in the past? And how big is the residue present in the processed tea?

This is based upon information I received first hand hand from a scientist at a multibillion dollar company that specializes is commercial pest control and sanitation. They had their own lab to study pesticides including efficacy, safety, application methods, etc.

The context of the my question was to determine the efficacy of different pesticides in high heat, high humidity environments. The conversation was limited to wettable powders and emulsifiable concentrates (ie, sprays).

I was told that in their studies most pesticides breakdown and are no longer effective after 2 weeks of heat, humidity, and sunlight like we have in the southern U.S. It seemed that heat and humidity were the two main causes for rapid loss of efficacy as they applied their findings to applications in commercial kitchens, even going so far as to completely readdress what pesticides were applied in commercial kitchens and dining rooms.

Note that these pesticides were not formulated to be applied to foodstuffs so I imagine these are stronger that what is applied agriculturally.

I was given a summary of their findings but this has long since been lost. The longest period that a pesticide was effective for in subtropical heat and humidity was 6 weeks. This was a wettable powder. Emulsifiable concentrates have the least lasting efficacy.

None of this is to say that the pesticides were no longer toxic after these times (chlordane, iirc, can remain toxic in soil for decades) but it should give an idea how rapidly these modern compounds breakdown.

[Sweetestdew]

thanks for sharing the conversation. it ended just when it was getting good though!

i wanted to hear about which pests her uncle sprays for

I know! but the convesation had already stopped once I had restarted it. I didnt want to do it twice

[Sweetestdew]

I am curious about what specific pesticides are used (by brand or chemical).

I have smelled beta-cyfluthrin (or its carrier agent) on some teas from Taiwan. It’s a nice sweet smell— like floral five spice— so I can see how it goes with teas but for someone like me who used to apply it, it’s an unmistakable smell.

I am too but she stopped responding and I had already restarted the conversation once, didnt want to do it twice.
I will visit her family again next spring and get better answers.