Scientists from the Missouri Botanical Garden helped convict a Missouri killer. The scientists compared juniper needles near the victim’s remains and on the suspect’s muddy hiking boots, matched them, and tied the suspect to the crime. Their role in the murder trial of Joseph Elledge, convicted in November 2021 of killing his wife in 2019 in Columbia, Missouri, will be outlined in an episode of “48 Hours,” to run 9 p.m. Saturday on CBS. The episode is called “The Tree That Helped Solve a Murder.” …The shallow grave where Ji’s bones were scattered was in an area that included a canopy of juniper trees. …Of the 20 or so needle samples found in the boots, they had five matches to three trees in the area. Three of those samples came from a tree right over the gravesite. Junipers happen to have a lot of genetic diversity, Edwards said. “And we matched their genotypes exactly,”