Dataset: Fern Observations

Block number-letter combination identifying Holt Research Forest major research area subdivisions (100m x 100m): number (west-east coordinate) + letter (north-south coordinate) used in Fern Observation Study.

Leaf breakage code, where breakage had removed upper part of leaf

Herbivory on sori on abaxial surface of fertile leaf; only recorded 2005-2011, 2019

Count of fertile leaves (spore-bearing leaves, sporophyllis) on the monitored plant

Count of fertile leaves on which sori were present but not yet mature. Only recorded for D. marginalis in years 2006-2012.

ID number associated with each study plant and written on flag (white plastic, metal wire support) with Sharpie pen (replaced as needed)

Count of leaves with herbivory in the form of a gall attributed to the larvae of an amthomyiid fly (Chirosia betuleti) where leaf development had been arrested by the formation of a rolled rachis forming a cluster of developing pairs of leaflets (a structure sometimes referred to a "mop-head").

Leaf lamina (blade) length

Latitude of sample subquadrat

Longitude of sample subquadrat

Leaf length: sum of longest leaf's petiole length and lamina length measurements (PET + LAM)

Category of leaf measured (longest or not)

Code used to indicate that plant was not found or found but not monitored a span of n number of years

Code identifying the category of plant observations

Petiole (stalk below leaflets) length

Code denoting the plant reproductive status at the start of monitoring in 2000

Count of pairs of leaflets (pinnae) in lamina (below terminal leaflet area at the leaf tip: only recorded in 2000-2011, 2019, 2023/24

Quadrat number assigned to each of four 50m x 50x areas within a block

Count of the number of pairs of leaflets on the longest fertile leaf with sori present (0 = terminal only). Only recorded in 2005, 2006, 2008-2011 for all longest fertile leaves and in 2019 for longest fertile leaves on focal plants (pcat = X).

Species abbreviation for the two species of fern monitored in this study.

Code for plant mortality status

First survey year for plant (when STATCODE = AL) or first survey year that plant is gone (when STATCODE = GY)

Count of sterile leaves (photosynthetic only, vegetative, trophophyllis) on the monitored plant and lacking spore bearing structures (sorus, pl sori) on the lower surface of the leaf (includes observations of broken leaves even though it is not known if the upper part of the leaf had spores)

ID code for study subquadrats

Code noting the presence or absence of reproductive structures on any of the leaves during current monitoring session.

Leaf type code indicating sterile (vegetative) or fertile (reproductive) functional status of the leaf measured; if not recorded assumed as TYPEPLANT (2000-2002 and 2004-2006).

Code used to describe crown shape of plants. Only recorded in years 2008-2024.

Width of lamina at about its midpoint

Year during which fall monitoring took place.

Subquadrat number assigned to minor block subdivisions (25m x25m), four per Quadrat, used for monitoring.