Meet the Horticultural Experts

Dr. Elena Vance, Ph.D.

Senior Horticulturist & Soil Scientist

school Ph.D. Plant Science, Cornell University (2004)workspace_premium Certified Professional Horticulturist (ASHS)

With 22 years of experience in horticultural research, Dr. Vance specializes in soil health, native plant ecology, and climate-adaptive gardening. Her soil pH research at Cornell University fundamentally changed how extension programs teach home gardeners to manage soil chemistry, and her field studies on mycorrhizal networks in Pacific Northwest forests are cited in university curricula across the country.

Dr. James Hartwell, Ph.D.

Plant Pathologist & Integrated Pest Management Specialist

school Ph.D. Plant Pathology, University of Florida (2008)workspace_premium Board Certified Entomologist (ESA)

Dr. Hartwell brings 18 years of applied plant pathology research to KnowTheYard. His field trials at the University of Florida helped develop resistance-breeding protocols now used commercially by nurseries across the Southeast. He has identified over 40 novel fungal pathogens affecting ornamental plants and is a recognized authority on nematode management in warm-season turfgrass.

Sarah Chen, MLA

Landscape Architect & Urban Horticulture Specialist

school Master of Landscape Architecture, Harvard GSD (2011)workspace_premium Registered Landscape Architect (CLARB)

Sarah Chen has spent 15 years at the intersection of landscape architecture and plant science, designing public gardens across 6 states and consulting on urban greening initiatives for municipal governments. Her work with the USDA Urban Forest program shaped federal guidelines for heat-island mitigation through strategic planting — turning data-driven canopy analysis into actionable policy. She brings the same evidence-based rigor to every KnowTheYard guide she reviews.