> If you happen to find sub lethal studies please post as maybe a study myself and others have not seen.

I already posted a long term study where bees were kept near oilseed rape. If there were sublethal effects they would certainly show up in a four year study. There was no difference between bees kept on oilseed, or not. However, significant losses occurred where varroa were not controlled and viruses got out of hand. This is the sort of study you asked for, got, and you should pay attention to the results.

> Besides losses also a comparisons of the bee population before and after winter were recorded. This offers the possibility to evaluate sublethal effects which potentially weakened colonies during winter. Factors with negative influence tendencies on wintering and factors to be excluded as triggers could be identified. Based on the current evaluations it was concluded: 

1. Between oilseed rape sites and non-oilseed rape sites no differences were found for colony losses neither for the overwintering quotient (= colony strength in autumn divided by colony strength in spring). 

2. Highly significant correlations were found between winter losses and the Varroa infestation levels in autumn. The risk for colony loss increases with the number of mites in the colony in autumn. 

3. Similarly the correlations between the infection with ABPV and DWV in autumn and winter losses were significant. 

4. No significant correlations were found for Nosema sp. infections. 

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