We present a study of flare rates, rotation periods, and spectroscopic activity indicators of 125 single stars within 15 parsecs and with masses between 0.1 and 0.3M_{sun} observed during the first year of the TESS mission, with the goal of elucidating the relationship between these various magnetically connected phenomena. We gathered multiepoch high-resolution spectra of each target, and we measured equivalent widths of the activity indicators helium I D3, H{alpha}, and the calcium infrared triplet line at 8542.09{AA}. We present 18 new rotation periods from MEarth photometry and 19 new rotation periods from TESS photometry. We present a catalog of 1392 flares. After correcting for sensitivity, we find the slope of the flare frequency distribution for all stars to have a standard value of {alpha}=1.98+/-0.02. We determine R_31.5, the rate of flares per day with energies above E=3.16x10^31^ergs in the TESS bandpass. We find that below a critical value of H{alpha}EW=-0.71{AA}, logR_31.5_ increases linearly with increasing H{alpha} emission; above this value, logR_31.5_ declines rapidly. The stars divide into two groups: 26% have H{alpha} in emission, high flare rates with typical values of logR_31.5_=-1.30+/-0.08, and have Rossby numbers <0.50. The remaining 74% show little to no H{alpha} in emission and exhibit logR_31.5_{<}-3.86, with the majority of these stars not showing a single flare during the TESS observations.

Cone search capability for table J/ApJ/905/107/table1 (Stellar properties, equivalent widths, and flare rate)