May Watts leading group of children wearing feather headbands in musical performance on steps outside of Thornhill (3.4077)

Date: 1950s
Type: Photographic image
Description:May Watts leading group of children wearing feather headbands in musical performance on steps outside of Thornhill
Extent: 1 photograph

May Watts instructing class in Thornhill classroom (3.4078)

Date: 1950s
Type: Photographic image
Description:May Watts instructing class in Thornhill classroom
Extent: 1 photograph

May Watts with Junior Forestry class outdoors (3.4079)

Date: 1952
Type: Photographic image
Description:May Watts with Junior Forestry class outdoors
Extent: 1 photograph

May Watts instructing class in Thornhill classroom (3.4080)

Date: 1950s
Type: Photographic image
Description:May Watts instructing class in Thornhill classroom
Extent: 1 photograph

Evergreen Nature Trail Guide, cover art (3.19462)

Date: 1940s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Proof for cover/page 1 including more detailed illustrations and layout with title for the The Morton Arboretum Evergreen Nature Trail Guide booklet. Key lines included.

Depicts illustrated map of trail through Spruces and Firs, Arbor Vitae, Larch, Pines, Junipers, Yew, and Hemlock Collections. Below map, stylized trees and two figures illustrated, standing next to sign "Evergreen Nature Trail".

Text at bottom of illustration:  "Trail Begins Here - Parking Number Two - Trail Ends Here"
Extent: 1 sheet

Botanical Terms Used in Describing Leaves, page 1 (3.19463)

Date: July 1944
Creator: Watts, May Theilgaard
Type: Drawing
Description:Sheet 1 of 4. Glossary of botanical terms and illustrations depicting labeled leaf silhouettes used for describing leaves, created to accompany "Botanical Terms Used in Describing Leaves" article featured in Morton Arboretum Bulletin of Popular Information. Descriptive text includes an introductory paragraph and details of leaf shapes. The remaining identifying text originally adhered to the board has detached and is no longer present.

Header: LEAVES ARE CALLED

Leaf terms depicted from top to bottom, left to right

• SIMPLE
• COMPOUND
  • pinnately-compound
  • palmately-compound, (or digitate)
  • ternately-compound, (or trifoliate)
  • doubly-compound (or bi-pinnate)

Leaf terms across bottom of page from left to right

• PERFOLIATE
• RADICAL
• SESSILE
• ALTERNATE
• OPPOSITE
• WHORLED

Extent: 1 sheet

Botanical Terms Used in Describing Leaves, page 2 (3.19464)

Date: July 1944
Creator: Watts, May Theilgaard
Type: Drawing
Description:Sheet 2 of 4. Glossary of botanical terms and illustrations used for describing leaves, created to accompany "Botanical Terms Used in Describing Leaves" article featured in Morton Arboretum Bulletin of Popular Information. Illustrations depict various over-lapping leaf silhouettes with additional small sketches of objects to explain each shape in a column on the left, and a glossary of terms describing the leaves in a column on the right. Descriptive text adhered to the board includes details of leaf shapes.

Header: A LEAF SHAPE IS CALLED:

Leaf shapes depicted from top to bottom, left to right:

• OBLONG
  • Silhouette of oblong shaped leaf with sketch of radio tube under stem
• OVAL
  • Silhouette of oval shaped leaf with sketch of tennis racket under stem
• OVATE
  • Silhouette of ovate shaped leaf with sketch of lit candle under stem
• OBOVATE
  • Silhouette of obovate shaped leaf with sketch of light bulb under stem
• ELLIPTIC
  • Silhouette of elliptic shaped leaf with sketch of an eye at stem
• CORDATE
  • Silhouette of cordate shaped leaf with sketch of a playing card at stem
• PELTATE
  • Silhouette of peltate shaped leaf with sketch of an umbrella under stem
• RENIFORM
  • Silhouette of reniform shaped leaf with sketch of a jelly bean under stem
• DELTOID
  • Silhouette of deltoid shaped leaf with sketch of a garden trowel under stem
• HALBERD-SHAPED
  • Silhouette of halberd-shaped leaf with sketch of a fish hook under stem
• LANCEOLATE
  • Silhouette of lanceolate shaped leaf with sketch of a carrot under stem
• OBLANCEOLATE
  • Silhouette of oblanceolate shaped leaf with sketch of a dart at stem
• SPATULATE
  • Silhouette of spatulate shaped leaf with sketch a canoe at stem
• LINEAR
  • Silhouette of linear shaped leaf with sketch a butter knife at stem

Extent: 1 sheet

Botanical Terms Used in Describing Leaves, page 3 (3.19465)

Date: July 1944
Creator: Watts, May Theilgaard
Type: Drawing
Description:Sheet 3 of 4. Glossary of botanical terms and illustrations used for describing leaves, created to accompany "Botanical Terms Used in Describing Leaves" article featured in Morton Arboretum Bulletin of Popular Information. Glossary of terms in 2 sections describe leaf tips and leaf bases in a column on the left. Illustrations depict various over-lapping leaf silhouettes with additional small sketches of objects to explain each shape in a column on the right. Descriptive text adhered to the board includes details of leaf tips and bases.

Section 1: A LEAF TIP IS CALLED:

Leaf tips depicted from top to bottom, left to right:

• ACUMINATE
  • Silhouette of acuminate shaped leaf tip with sketch of long pointed witches hat
• ACUTE
  • Silhouette of acute shaped leaf tip with sketch of clown hat angled less than 90 degrees
• MUCRONATE
  • Silhouette of mucronate shaped leaf tip with sketch of beret with small tip at the center
• CUSPIDATE
  • Silhouette of cuspidate shaped leaf tip with sketch of a hat with a sharply pointed tip
• OBTUSE
  • Silhouette of obtuse shaped leaf tip with sketch of a pope's hat
• ROUNDED
  • Silhouette of rounded shaped leaf tip with sketch of a baseball cap
• TRUNCATE
  • Silhouette of truncate shaped leaf tip with sketch of a top hat
• EMARGINATE
  • Silhouette of rounded shaped leaf tip with sketch of a queen's crown

Section 2: A LEAF BASE IS CALLED:

Leaf bases depicted from top to bottom, left to right:

• TRUNCATE
  • Silhouette of truncate shaped leaf base with sketch of a skirt cut straight across
• CORDATE
  • Silhouette of cordate shaped leaf base with sketch of a men's Elizabethan breeches
• OBLIQUE
  • Silhouette of oblique shaped leaf base with sketch of a golf pants of unequal length
• AURICULATE
  • Silhouette of auriculate shaped leaf base with sketch of a pants gathered at ankles with droopy ear lobe-like shape
• ROUNDED
  • Silhouette of rounded shaped leaf base with sketch of an apron over a skirt
• ACUTE
  • Silhouette of acute shaped leaf base with sketch of tapered riding pants
• ACUMINATE
  • Silhouette of acuminate shaped leaf base with sketch of a pirate with a peg leg

Extent: 1 sheet

Botanical Terms Used in Describing Leaves, page 4 (3.19466)

Date: July 1944
Creator: Watts, May Theilgaard
Type: Drawing
Description:Sheet 4 of 4. Glossary of botanical terms and illustrations used for describing leaves, created to accompany "Botanical Terms Used in Describing Leaves" article featured in Morton Arboretum Bulletin of Popular Information.  Illustrations depict various over-lapping leaf silhouettes in a column on the left. Glossary of terms in 2 sections describe the leaves in a column on the right. Descriptive text adhered to the board includes details of leaf margins and veins, and an unillustrated section about leaf surface types and characteristics.

Section 1: A LEAF MARGIN IS CALLED:

Leaf margins depicted from top to bottom, left to right:

• LOBED
• UNDULATE (repand)
• SINUATE
• CRENATE
• CRENULATE
• DENTATE
• DENTICULATE
• SERRATE
• SERRULATE
• DOUBLY-SERRATE
• ENTIRE
• REVOLUTE

Section 2: THE VEINING OF A LEAF IS CALLED:

Leaf veins depicted from top to bottom, left to right:

• PARALLEL
• PINNATE
• PALMATE
• DICHOTOMOUS

Extent: 1 sheet

January Calendar (3.19467)

Date: 1940s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Calendar for the month of January consisting of five rows and seven columns depicting days and dates from Sunday through Saturday, the 1st through the 31st. Each square has a date plus illustration and text, some of which anticipates the coming Spring and some which show reminders of the past year.

Header: January

Text and illustrations, from top to bottom, left to right:

• (Friday, 1) [image of dogwood stems and buds] flowering dogwood is ready for Spring
• (Saturday, 2) [image of hemlock needles and cones] small cones drip from the hemlock tips - 
• (Sunday, 3) [image of unidentified stems and fruit]
• (Monday, 4) [image of one chickadee and a birdhouse]
• (Tuesday, 5) [image of two chickadees and a birdhouse] chikca-dees stay to crack their seeds
• (Wednesday, 6) [image of evergreen needles and star magnolia stems and buds] star mag-nolia buds are pale against evergreens
• (Thursday, 7) [image of long-eared owl on branch of Norway spruce] long-eared owls look down from Norway spruce trees
• (Friday, 8) [image of 2 pellets on ground beneath evergreen branch] 2 pellets under an owl roost contain skeletons of 2 deer mice
• (Saturday, 9) [image of small animal bones on ground] when an owl pellet is pulled apart, evidence of sudden death is re-vealed
• (Sunday, 10) [image of euonymus stems and fruit] Euonymus still holds some of the "little hearts bursting with love"
• (Monday, 11) [image of birch stems, cones, and catkins] wind and birds have shattered birch cones but catkins are ready for Spring
• (Tuesday, 12) [image of zumi crabapple stems and fruit] Zumi crabs still hold their fruit
• (Wednesday, 13) [image of one cardinal and a birdhouse] the cardinal is back now that we have sunflower seeds again
• (Thursday, 14) [images of canker-worms on a dogwood twig] on a dogwood twig, canker worms are ready for Spring
• (Friday, 15) [images of evergreens and a hawthorn] hoar frost is on the hawthorns ---
• (Saturday, 16) [image of redbud stems, buds, and fruit] on red-bud, flower buds are ready for next Spring, and pods recall last Spring's flowers
• (Sunday, 17) [image of a bird on a tree branch]
• (Monday, 18) [image of sycamore trunks and branches] sycamore bark
• (Tuesday, 19) [image of trees and a trail] evergreen trail
• (Wednesday, 20) [image of rhododendron stems and leaves] Rhododendron leaves pointing down say it's COLD!
• (Thursday, 21) [image of a white Oak] white oaks hold last summer's leaves on lower branches
• (Friday, 22) [image of a Norway spruce] Norway spruce holds long cones
• (Saturday, 23) [image of pixie-cup lichens through a magnifying glass] there are Pixie-cup lichens in the spruce plot
• (Sunday, 24) [image of two ostrich ferns] the fertile fronds of ostrich fern stand stiff and dark
• (Monday, 25) [image of American cranberry-bush stems and fruit] high-bush cranberry wears puffs of snow
• (Tuesday, 26) [image of winter wren in brush] the winter wren weaves through low brush
• (Wednesday, 27) [image of hazel stems and catkins] hazel catkins feel softer
• (Thursday, 28) [image of vernal witch-hazel and close-up of flower] vernal witch hazel is in bloom
• (Friday, 29) [image of one set of raccoon tracks] raccoon tracks are plentiful after a mild night
• (Saturday, 30) [image of two sets of deer mouse tracks with trail mark between] white-footed deer mouse hops past
• (Sunday, 31) [image of three sets of Junco bird tracks] juncoes hop too

Extent: 1 sheet

Yellow Pond Lily (3.19469)

Date: 1940s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Two illustrations of a yellow pond lily, depicting leaves and flowers with identifying text below each image. Image "A" shows the flower about to open on the first day, and image "B" shows the second day with flower fully open.

Header: yellow pond lily

Plants and text as depicted from left to right:

• A - For one day the opening flower offers insects a small entrance, filled with the stigma reader for pollen from a flower like B [arrow pointing right to next column of text]
• B - On the second day the flower opens wide, and its stamens burst with pollen, ready to be carried by insects to a flower like A [arrow pointing left back to text in the first column]

Extent: 1 sheet

Some New England Trees (3.19470)

Date: 1940s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Illustrations of needles and cones for two types of trees found in New England.

Header: Some New England trees inhabit the mountain tops in the Smokies

Illustrations, top to bottom:

• red spruce
• hemlock

Extent: 1 sheet

An Example of Parallel Species (3.19471)

Date: 1940s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Illustrations comparing two parallel species of trees, one in America and one in Europe. Illustrations depict a branch with leaves and fruit.

Header: An example of parallel species

Illustrations from left to right:

• one in southeastern America
  • ironwood -- Ostrya virginiana
• one in Europe
  • European hornbeam -- Ostrya carpinifolia

Extent: 1 sheet

Three Trees Whose Relatives Are Largely In the Tropics (3.19472)

Date: 1940s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Illustrations of three types of leaves layered one on top of the other.

Text at center left: Three trees whose relatives are largely in the tropics

Illustrations from center outward:

• Silver Bell
• Fringe Tree
• Paw-paw

Extent: 1 sheet

A Bur Oak Twig (3.19473)

Date: 1940s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Detailed illustration of a single bur oak twig with identifying text.

Text: a bur oak twig
Extent: 1 sheet

Four Plants Whose Relatives Are In Eastern Asia (3.19474)

Date: 1940s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Illustrations of leaves of four types of plants, including two with flowers.

Upper left text: Four plants whose relatives are in eastern Asia

Plants depicted, from left to right:

• tulip tree
• sweet gum
• Jeffersonia
• May apple

Extent: 1 sheet

Two Cattails (3.19475)

Date: 1940s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Illustrations of two cattails with identifying text. Graphite sketches of the plants are visible at each image.

Drawings as depicted from left to right:

• cattail with pistils and stamens identified
• cattail with seeds identified

Extent: 1 sheet

Shortia Galacifolia, Oconee Bells (3.19476)

Date: 1940s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Illustration of Oconee bells plant with identifying text, depicting leaves, five flowers, and one bud. Writing in graphite underneath includes identifying text.

Text: Shortia galacifolia - Oconee bells
Extent: 1 sheet

Vernal Witch-hazel (3.19477)

Date: mid 20th century
Creator: Watts, May Theilgaard
Type: Drawing
Description:Illustration of the Vernal witch-hazel plant, including three detailed views and some descriptive text. Background sketches include trees at top and center, and shrubs at center and bottom.

Header: VERNAL WITCH-HAZEL, HAMAMELIS vernalis

Illustrations as depicted, from top to bottom, left to right:

• a single pistil, labeled PISTIL
• two stamens, front view and side view, labeled STAMEN
• a single twig in bloom
• a flower 

Extent: 1 sheet

Skunk Cabbage (3.19478)

Date: mid 20th century
Creator: Watts, May Theilgaard
Type: Drawing
Description:Illustration of the skunk cabbage plant with environment, including three detailed views of flowering parts. Background sketches include a willow tree, cattails, and skunk cabbage in and near water.

Header: SKUNK CABBAGE

Illustrations as depicted, from top to bottom, left to right:

• enlarged view of the spathe
• enlarge view of a single flower
• enlarged view of the spadix

Extent: 1 sheet

Morton Arboretum Map (3.19479)

Date: 1943
Creator: Watts, May Theilgaard
Type: Map
Description:2014 reprint of The Morton Arboretum's first color map, circa 1943.

Detailed map of Arboretum grounds, showing roads, paths, landscaping, shelters, structures, enlargement of some specific features, hedge garden, some specific trees, and trails with markers numbered 1 - 42. Other features include a scale, a calendar, and a compass rose consisting of directions depicted with leaves. A highly ornamental border includes grid marks, as well as drawings of animal tracks and detailed drawings and labels of plants. The Morton Arboretum encompassed 813 acres at time of map. 
 
Extent: 1 sheet

Morton Arboretum Map: Preliminary Drawing for Colored Map (3.19480)

Date: 1943
Creator: Watts, May Theilgaard
Type: Drawing
Description:Preliminary drawing for detailed colored map of Arboretum grounds that was printed in 1943, showing roads, paths, landscaping, shelters, enlargement of some specific features, hedge garden, and center of hedge garden. Blank spaces indicate water and text placement. Tree symbols show exceptional specimens on east and west sides. The Morton Arboretum encompassed 813 acres at time of map. Drawing is in two pieces.
Extent: 2 sheets

Morton Arboretum Map (3.19481)

Date: 1943
Creator: Watts, May Theilgaard
Type: Map
Description:Detailed map of Arboretum grounds, showing roads, paths, landscaping, shelters, structures, enlargement of some specific features, hedge garden, some specific trees, and trails with markers numbered 1 - 42. Other features include a scale, a calendar, and a compass rose consisting of directions depicted with leaves. A highly ornamental border includes grid marks, as well as drawings of animal tracks and detailed drawings and labels of plants. Some replacement illustration and text has been adhered to the map. The Morton Arboretum encompassed 813 acres at time of map. One section is partially missing.
Extent: 1 sheet

Emergent Plant Series: #1, Submerged Plant Stage (3.19485)

Date: 1950s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Part of a series of numbered illustrations about the stages of pond growth. This material includes an aerial view of a pond with trees and hills in background, and a cross-section view of five types of submerged aquatic plants attached to pond bottom.

Header: SUBMERGED PLANT STAGE / PLANTS ATTACHED TO BOTTOM / only their flowers reach the surface

Drawings and text from top to bottom, left to right:

• pond and surrounding landscape
• cross-section:
  • WATER WEED--Elodea canadensis
  • EEL GRASS--Vallisneria spiralis
  • PONDWEED--Potamogeton crispus
  • HORNWORT--Ceratophyllum demersum
  • WATER MILFOIL--Myriophyllum spicatum

Extent: 1 sheet

Emergent Plant Series: #2, Floating-Leaf Plant Stage (3.19486)

Date: 1950s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Part of a series of numbered illustrations about the stages of pond growth. This material includes an aerial view of a pond showing some plants at the surface of its bay with trees and hills in background, and a cross-section view of aquatic plants attached to pond bottom, with leaves and flowers of shallower plants extended to water's surface.

Header: FLOATING-LEAF PLANT STAGE / PLANTS ATTACHED TO BOTTOM / leaves and flowers floating at surface

Drawings and text from top to bottom, left to right:

• pond and surrounding landscape
• cross-section [divided into 4 sections]:
  • FLOATING LEAF ZONE
    • water lily
    • cow lily
  • SUBMERGED PLANT ZONE
    • water weed
    • eel grass
    • pondweed
    • hornwort
    • water milfoil
  • SUBMERGED PLANT STAGE
  • FLOATING LEAF ZONE

Extent: 1 sheet

Emergent Plant Series: #3, Emergent-Plant Stage (3.19487)

Date: 1950s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Part of a series of numbered illustrations about the stages of pond growth. This material includes an aerial view of a pond showing some plants at the surface of its edges and its bays with trees and hills in background, and a cross-section view of aquatic plants attached to pond bottom, with leaves and flowers of shallower plants extended up to and above the water's surface.

Header: EMERGENT-PLANT STAGE / PLANTS UPRIGHT / only roots and base under water

Drawings and text from top to bottom, left to right:

• pond and surrounding landscape
• cross-section [divided into 6 sections]:
  • EMERGENT ZONE
    • cat-tails
    • arrowhead
    • bur reed
    • pickerel weed
    • bullrush
  • FLOATING-LEAF ZONE
  • SUBMERGED-PLANT ZONE
  • SUBMERGED-PLANT ZONE
  • FLOATING-LEAF ZONE
  • EMERGENT ZONE

Extent: 1 sheet

Emergent Plant Series: #4, Pioneer Tree Stage (3.19488)

Date: 1950s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Part of a series of numbered illustrations about the stages of pond growth. This material includes an aerial view of a pond showing trees and plants at its edges and bays with additional trees and hills in the background, and a cross-section view of aquatic plants attached to pond bottom, with leaves and flowers of shallower plants extended up to and above the water's surface.

Header: PIONEER TREE STAGE / WILLOWS ARE FIRST

Drawings and text from top to bottom, left to right:

• pond and surrounding landscape
• cross-section [divided into 4 sections]:
  • Tree Zone
    • willow
    • silver maple
  • Emergent plant one
  • Floating leaf zone
  • Submerged plant zone

Extent: 1 sheet

Emergent Plant Series: #5, Lowland Forest Stage (3.19489)

Date: 1950s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Part of a series of numbered illustrations about the stages of pond growth. This material includes an aerial view of a pond showing trees and plants at its edges and bays with additional forest trees and hills in the background, and illustrations of trees and a cross-section view of aquatic plants attached to pond bottom.

Header: LOWLAND FOREST STAGE / TREES THAT TOLERATE WET FEET

Drawings and text from top to bottom, left to right:

• pond and surrounding landscape
• cross-section [divided into 9 sections]:
  • LOWLAND FOREST ZONE
    • elm
    • ash
    • hackberry
    • linden
  • PIONEER TREE ZONE
  • EMERGENT-PLANT ZONE
  • FLOATING-LEAF ZONE
  • SUBMERGED PLANT ZONE
  • FLOATING-LEAF ZONE
  • EMERGENT-PLANT ZONE
  • PIONEER TREE ZONE
  • LOWLAND FOREST ZONE

Extent: 1 sheet

Emergent Plant Series: #6, Climax Forest Stage (3.19490)

Date: 1950s
Creator: Watts, May Theilgaard
Type: Drawing
Description:Part of a series of numbered illustrations about the stages of pond growth. This material includes a view of a pond in the center with forest trees and hills in the background, and a cross-section of illustrations of forest trees, and trees and emergent plants of the water's edge.

Header: CLIMAX FOREST STAGE / THE PERMAMENT FOREST of the REGION

Drawings and text from top to bottom, left to right:

• pond and surrounding landscape
• cross-section [divided into 7 sections]:
  • CLIMAX FOREST
    • red oak
    • white oak 
    • hickory
  • LOWLAND FOREST ZONE
    • elm
    • ash
    • hackberry
    • linden
  • PIONEER TREE ZONE
    • willow
    • silver maple
  • EMERGENT ZONE
    • cat-tails
    • arrowhead
    • bur reed
    • pickerel weed
    • bull-rush
  • PIONEER TREE ZONE
  • LOWLAND FOREST ZONE
  • CLIMAX FOREST

Extent: 1 sheet

Four Oaks (3.19491)

Date: 1940 – 1959
Creator: Watts, May Theilgaard
Type: Drawing
Description:Illustrations of four oaks: Chinkapin oak, Swamp white oak, White oak and Bur oak. Each tree is illustrated by silhouette, and is accompanied by an outline of its leaf and drawings of its twig with a winter bud and its acorn.
upper left: Quercus muehlenbergii, Chinkapin oak
upper right: Quercus bicolor, Swamp white oak
lower left: Quercus alba, White oak
lower right Quercus macrocarpa, Bur oak
Extent: 1 sheet

Growth of Pond: Submerged Plant Stage (3.19492)

Date: 1940 – 1950
Creator: Watts, May Theilgaard
Type: Drawing
Description:Part of a series of illustrations about the stages of pond growth. This material includes an aerial view of a pond with two bays and a cross-section view of five types of submerged aquatic plants attached to pond bottom.

Header: SUBMERGED PLANT STAGE / PLANTS ATTACHED TO BOTTOM / only their flowers float on the surface

Drawings and text from top to bottom, left to right:

• Pond: sheltered bays are first to show vegetation
• CROSS-SECTION of MARGIN
  • Water milfoil--Myriophyllum spicatum
  • Water weed--Elodea canadensis
  • Eelgrass--Vallisneria spiralis
  • Pondweed--Potamogeton crispus
  • Hornwort--Ceratophyllum demersum

Extent: 1 sheet

Growth of Pond: Floating Plant Stage (3.19493)

Date: 1940 – 1950
Creator: Watts, May Theilgaard
Type: Drawing
Description:Part of a series of illustrations about the stages of pond growth. This material includes an aerial view of a pond with some plants showing at the surface of its bays and a cross-section view of aquatic plants attached to pond bottom, with leaves and flowers of shallower plants extended to water's surface.

Header: FLOATING PLANT STAGE / PLANTS ATTACHED TO BOTTOM / LEAVES AND FLOWERS FLOATING

Drawings and text from top to bottom, left to right:

• Pond
• CROSS-SECTION of MARGIN
  • Accumulation from submerged plants makes margin more shallow [arrow pointing up to shallower plants]
  • Submerged plants move out to deeper water [arrow pointing right to deeper plants]

Extent: 1 sheet

Growth of Pond: Emergent Plant Stage (3.19494)

Date: 1940 – 1950
Creator: Watts, May Theilgaard
Type: Drawing
Description:Part of a series of illustrations about the stages of pond growth. This material includes an aerial view of a pond with some plants showing at the surface of its edges and its bays, and a cross-section view of aquatic plants attached to pond bottom, with leaves and flowers of shallower plants extended up to and above the water's surface.

Header: EMERGENT PLANT STAGE / PLANTS UPRIGHT / only roots and base under water

Drawings and text from top to bottom, left to right:

• Pond
• CROSS-SECTION of MARGIN [divided into 3 sections]:
  • Emergent Plant Zone
    • cat-tails
    • arrowhead
    • bur reed
    • pickerel weed
    • bullrush
  • Floating Plant Zone
    • white water lily
    • cow lily
  • Submerged Plant Zone
    • pondweed
    • eel grass
    • water milfoil
    • etc.

Extent: 1 sheet

Growth of Pond: Pioneer Tree Stage (3.19495)

Date: 1940 – 1950
Creator: Watts, May Theilgaard
Type: Drawing
Description:Part of a series of illustrations about the stages of pond growth. This material includes an aerial view of a pond with trees and plants showing at its edges and bays, and an illustration of a tree and cross-section view of aquatic plants attached to pond bottom, with leaves and flowers of shallower plants extended up to and above the water's surface.

Header: PIONEER TREE STAGE / WILLOWS ARE FIRST TO ARRIVE

Drawings and text from top to bottom, left to right:

• Pond
• [divided into 4 sections]:
  • TREE ZONE
    • willows
    • silver maples
  • EMERGENT PLANT ZONE
  • FLOATING-LEAVED ZONE
  • SUMERGED PLANT ZONE

Extent: 1 sheet

Arboretum Landscape Teaching Aid Series: The Great Ice Sheet (3.19496)

Date: mid 20th century
Creator: Watts, May Theilgaard
Type: Drawing
Description:Primarily textual teaching aid depicting Arboretum landscape. This material shows how the Arboretum Hills were pushed from Canada and Wisconsin.

Header: THE GREAT ICE SHEET brought THE ARBORETUM HILLS from Canada to Wisconsin

Text and illustrations from top to bottom:

• [Depicted in stylized scroll with an illustration of a body of water between two hills] The Record: The Arboretum hills are made of unsorted clay, sand, gravel and boulders.
• Interpreting the record:
  • 1) Ice-deposited material is an unsorted material [arrow pointing right to illustration of ice-deposited material] Water-deposited material is sorted into layers [arrow pointing right to illustration of water-deposited material] The Arboretum hills are made of material dumped by the melting ice.
  • 2) Granite boulders are found in this material. No granite bed-rock is found within 200 miles of here.
  • 3) Rocks frozen into a glacier are flattened and scratched like this [arrow pointing left to illustration of a rock] (see rock at end of table) Water-borne rocks are rounded and smoothed.

Extent: 1 sheet

Arboretum Landscape Teaching Aid Series: A River Emerged From Under A Glacier (3.19497)

Date: mid 20th century
Creator: Watts, May Theilgaard
Type: Drawing
Description:Primarily textual teaching aid depicting Arboretum landscape. This material shows the origin of gravel pits at the Arboretum.

Header: A RIVER EMERGED FROM UNDER A GLACIER

Text and illustrations from top to bottom:

• [Depicted in stylized scroll with illustration of a steam shovel in gravel pit] The Record: There are several old gravel pits in the Arboretum.
• Interpreting the record:
  • 1) A river running under a glacier is confined to a narrow channel, and is, therefore swift. Because of its swiftness it can carry gravel.
  • 2) When such a river comes out from under the ice it spreads out and slows down. Slow moving water can carry only fine material. Therefore the river dropped its heavy material.
  • 3) When men found these places they dug the gravel out.

Extent: 1 sheet