The release of transgenes into the environment by transgenic plant species is a significant ecological concern, and consequently a containment method for these genetically modified organisms is highly sought after. For poplar trees, an option for containment is to produce trees that do not flower and therefore cannot spread genetic material. The technique RNA interference (RNAi) is used to silence specific genes, and can be used in poplars to target floral developmental genes. Along with RNAi transgenes, the gene Heat Shock Promoter:FLOWERING LOCUS T (HSP:FT) is inserted into poplar trees to promote early flowering, allowing one to expedite the study of the effects of RNAi. Before one is able to study these effects, however, they must confirm that the poplars with HSP:FT insertion can successfully flower when the floral developmental genes are not targeted by RNAi, so that when RNAi transgenes are introduced, an absence of flowering can be attributed to RNAi rather than some other external factor. The goal of this study was to determine if there is a minimum level of FLOWERING LOCUS T gene (FT) expression required to induce flowering in poplar trees. Based on the results of this study, there appears to be a direct correlation between FT expression and flowering in poplar trees. The methods used in this study led to qualitative results that indicated only the presence or absence of FT expression, so the next step is to quantify the amount of FT present in the flowering poplar constructs using quantitative PCR (qPCR).