So, a while back, I built up a list of "impressive trees", trying to come up with ideas for trees as gifts. The goal was to find the most "impressive" trees, in terms of height, diameter, mass, or some combination thereof, with a bit of extra bias toward the unusual or things that can grow in extreme climates (hence the Canary Island Dragon Tree made it, despite an unimpressive height and a moderate 4.5m max diameter, because of its unusual shape and the fact that it can thrive in very dry locations. Canary Island Pine, same reason -- max 60m height, unimpressive diameter, but can tolerate a ridiculously dry climate)

My current list is here.

Since most of the biggest trees are conifers (the giant Eucalyptus species of Tasmania being the only real contenders for the top slots), I figured you all might have an idea what exactly I forgot, or catch any mistakes I might have made. Here's just the species names (a lot more info is in the spreadsheet than just the name -- genus/species, family common name, common widths and heights, max widths and heights, growth rate, sun needs, soil needs, rainfall, bark, leaves, flowers, fruit, wood, and general comments):

Giant Sequoia

Coast Redwood

Tasmanian Mountain-Ash

Messmate Stringybark

Rainbow Eucalyptus/Mindanao Gum

Alpine Ash/Woolybutt

Karri

Blue Gum

Manna Gum

Red Tingle

Western Redcedar

Coast Douglas-Fir

Sitka Spruce

Alerce/Fitzroya

Sugar Pine

California Incense Cedar

Kauri

Sugi

Kahikatea

Red Mahogany

Ceiba/Kapok/White Silk Cotton Tree

Almaciga/Dayungon

Taiwania/Formosan Redwood

Australian Red Cedar

Baobab

Sacred Fig

Montezuma Cypress

LawsonÂs Cypress (Port Orford cedar)

Western hemlock

Coast Grand Fir

Nordmann Fir

Jequitiba

Noble Fir

California Red Fir

European/Sweet/Spanish Chestnut

Canary Islands Dragon Tree

Canary Island Pine

By a family breakdown:

Cypress x9

Eucalyptus x8

Fir x4

Pine x2

Kauri x2 (a couple similar species grouped together)

Mahogany x2

Douglas Fir x1

Spruce x1

Hemlock x1

Baobab x1 (but several similar species grouped together)

Fig x1

Beech x1

Podocarpaceae x1

Malvaceae x1

Lecythidaceae x1

Ruscaceae x1