While it's good question and should be asked, one should keep in mind that the Torah's overall approach doesn't always match up with what we call "facts". There was no laboratory when it was written and even if it did exist, all over there are clear proofs that the Torah works based on mesorah which means what one learned from their rebbe who learned from his rebbe...back to moshe rabbeinu.
For example, with regards to milk and meaty taste transfers (basar bechalav), the Rema states that a [milk drop in a meaty stew] is neutralized if there is a 1/60 majority of the stew. Rema 98:1.
If you put the stew under a microscope and tested for milk, it may or may not show sign of lactose. But not matter what your findings are, the halacha will still stand.
Same with salting meat to get the blood out. After salting and rinsing the meat, one can very well find traces of what scientifically one would call blood.
Back to your question, the two sides are differing from their understanding as it was taught to them and not how it is observed by a horticulturist.