[16] Most adult timber rattlesnakes found measure less than 115 cm (45 in) in total length and weigh between 500 and 1,500 g (1.1 and 3.3 lb), often being towards the lower end of that range.

Holt (1924) mentions a large specimen caught in Montgomery County, Alabama, which had a total length of 159 cm (62.5 in) and weighed 2.5 kg (5.5 lb).

The museum at Amana Colony, Iowa, asserts that one founding family lost their firstborn, a daughter, at the age of three, due to a rattlesnake bite she received while playing on a woodpile in the 19th century.

[31] During the winter, timber rattlesnakes brumate in dens and limestone crevices, often together with copperheads (Agkistrodon contortrix) and rat snakes (Pantherophis alleghaniensis, P. obsoletus, and P.

[35] Timber rattlesnakes have also been found to leave dens multiple times in midwinter to briefly bask.

[42] The primary foods by genera of timber rattlesnakes were as follows: Peromyscus (33.3%), Microtus (10.9%), Tamias (qv) (10.6%), Sylvilagus (10.4%), Sigmodon (5.3%) and Sciurus (4.2%).

Several birds, although always secondary to mammals, are also known to be hunted, mainly ground-dwelling species such as bobwhites, but also a surprising number of passerines.

[44] Potentially, this is one of North America's most dangerous snakes, due to its long fangs, impressive size, and high venom yield.

[46] Cist (1845) described how he lived in western Pennsylvania for many years, and the species was quite common there, but in all that time, he heard of only a single death resulting from its bite.

[6] Considerable geographic and ontogenetic variation occurs regarding the toxicity of the venom, which can be said for many rattlesnake species.

Four venom patterns have been described for this species: Type A is largely neurotoxic, and is found in various parts of the southern range.

It is analogous to the neurotoxins found in the venoms of several other rattlesnake species, and when present, contributes significantly to the overall toxicity.

[49] That state's legislature praised "...a proud contribution by the eighth grade class at Romney Middle School, from West Virginia's oldest county, in West Virginia's oldest town, to have been instrumental in making the timber rattlesnake the state reptile..."[50] This snake became a prominent symbol of American anger and resolve during the American Revolution due to its fearsome reputation.

In the 18th century, European-trained doctors and scientists had little firsthand experience with or information on timber rattlesnakes,[51] and treatment of their bites was poorly effective.

The motto Nemo me impune lacesset (with the verb in the future tense) appears above a Crotalus horridus on a 1778 $20 bill from Georgia as an early example of the colonial use of the coiled rattlesnake symbol, which later became famous on the Gadsden flag, a flag that has been used by advocates of libertarianism, individualism, and small government.

[54] The timber rattlesnake is listed as endangered in New Jersey,[55] Ohio, Vermont, Connecticut, Massachusetts,[56] Virginia,[57] Indiana,[58][59] and New Hampshire.

The town of Westborough paid 13 men two shillings per day to rid a local hill of snakes in 1680.

[67] Since that time their habitat has been reduced to the Blue Hills south of Boston, the Berkshires in Western Massachusetts, and parts of the Connecticut River Valley, notably in the area of the Holyoke Range.

[68] In September 2021, a five-foot long timber rattlesnake was recorded on video on a trail in the Blue Hills Reservation.

[69] Timber rattlesnakes have already been extirpated in Maine and Rhode Island and only one population remains in New Hampshire.