Andrew The Arborist

09/28/2026

I explored a nice Wissahickon Schist outcropping along I-76, one of the busiest highways in the area. This exposed, rocky outcropping supports few woody plants because of the shallow soils — even Tree-of-Heaven was struggling to grow up here. However, these are favorable conditions for many native grassland species, including some rare ones!

I found some Eupatorium torreyanum, Trichostema dichotomum, Anatherum virginicum, Woodsia obtusa, and many more. I’ve been exploring more of these remaining grasslands in southeast PA lately, and having a lot of fun learning about these herbaceous species!

09/25/2026

09/15/2026

Native Goldenrods (Solidago spp.) are incredibly valuable for many insects including caterpillars, wasps, bees, and butterflies. They are a larval host plant for more species of butterflies and moths, and support more specialist bees than any other herbaceous plant in my area (southeast Pennsylvania).

They bloom from mid-to-late summer through fall, and pair well with native Asters (Symphyotrichum spp.) as well as other fall bloomers! They are just too important to leave out of your yard!

They are often blamed for fall allergies, but their pollen grains are quite large and sticky, meaning they aren’t easily airborne and are unlikely to be inhaled. Instead, wind-pollinated plants like Ragweed are more likely to cause hay fever.

What species of goldenrod have you planted?

09/12/2026

A monoculture of over 400 swamp white oaks (Quercus bicolor) was planted at the 9/11 memorial in NYC. The trees receive extensive care by a team of arborists, and their presence helps enhance the memorial space.

09/08/2026

Last week, it was announced that the museum at the Academy of Natural Sciences would close at the end of this month. This ~200 year old historic museum has inspired awe in our children, provided education to folks of all ages, and reminded Philadelphians and tourists how special life on this planet is.

You can help save the museum — there are certainly ways to make it happen, we just have to put the pressure on! Visit the link in my bio to be taken to save-the-academy.org and follow the items on the checklist. Follow savetheacademy and Sarah McAnulty for updates!

08/23/2026

These are some great native plant options for moist or wet soils in the northeastern US / southeastern Canada! Check out BONAP’s county range maps for more information on their native ranges.

08/18/2026

One effective way to control Ailanthus altissima (Tree-of-Heaven) is to use the Hack-and-Squirt method, where you make several gashes into the tree’s sapwood at a downward angle and fill the gash with an appropriate herbicide. The herbicide should then be taken in by the tree, translocated to the roots, and ideally leads to death within 1-3 months or so.

Tree-of-Heaven is unfortunately quite difficult to remove without using herbicide. Cutting one down before treating with herbicide will often result in many stems suckering from its extensive root system.

Our efforts to control this tree in this woodland is part of a larger effort to remove invasive species and restore native tree and shrub species that support more wildlife and ecosystem function.

More info here: https://extension.psu.edu/using-hack-and-squirt-herbicide-applications-to-control-unwanted-trees/

08/13/2026

Register Here: tinyurl.com/HNPAndrewConboy

Andrew Conboy Andrew The Arborist built a native plant movement in his own hometown, one tree, one neighbor, one project at a time.

Hear how you can do the same in our upcoming webinar, Lead the Change, August 20th at 12pm ET.

Can’t make it live? A recording will be available through September 20, 2026 for those who register for the event.

08/10/2026

Mountain Mint (Pycnanthemum species) attract a wide range of unique pollinators to their wonderful, fragrant flowers, and in my opinion, are a must-have for our landscapes! While they don’t serve as a host plant for many butterfly and moth caterpillars, their flowers draw in all sorts of insects that you may not see any other time of year.

There are many native Mountain Mint species in eastern North America and one species in California. Some of them can be a bit aggressive in certain garden settings, while others tend to form smaller, non-spreading clumps. They’re great for helping to naturalize some areas, and are deer resistant!

08/05/2026

These native long horned bees (genus Melissodes) are specialists that feed on pollen of plants in the Asteraceae (sunflower and aster family)! These bees show up each year when the sunflowers start blooming.