hybrid - The Scott Arboretum of Swarthmore College

Transcription

hybrid - The Scott Arboretum of Swarthmore College
HYBRID
Spring 2014
Scott Arboretum archives
THE SCOTT ARBORETUM OF SWARTHMORE COLLEGE
A view of Parrish
Hall through the
Lilac Collection in
late April
Spring in the Crum Woods
I feel exceedingly gratified to announce we
completed paying the balance owed on the Wister
Education Center and Greenhouse by the end of 2013,
six months ahead of the July 2014 deadline.
This final fundraising push was made in honor of
Dave Melrose and in Dave Melrose style we completed
the task. With generous support and generous planned
gifts, we accomplished this goal despite the significant
drop in our endowment performance the last five years
after the “Great Recession” set in. We did it thanks to
our loyal supporters who have generously responded
for many years now, including 2013, to our annual
18"w
appeals. As of this writing, 190 donors responded in
Dave Melrose Headhouse
This room is named in honor of Dave Melrose (1918-2010) who
gave over 40 years of service to the Scott Arboretum.
5.0"h
Dave Melrose (1977)
Dave began working here in 1959 and by 1967 was appointed
Assistant Director of the Scott Foundation, as the Arboretum was
known then. In 1982-1983 he served as Acting Director of the
Scott Foundation. Although he retired in 1984 as Assistant
Director of Physical Plant, Grounds, and Assistant Director of the
Scott Foundation, he continued working for the Arboretum part-time
until 2003.
Dave's education as a gardener began as a child working with his father who was head
gardener of the DeForest estate on Long Island. He earned an associate's degree in
horticulture at Cornell University and spent two years at the New York Botanical Garden
learning from T. H. Everett (1984 Scott Medal recipient). He enlisted in the Army Air
Corps during World War II, married his high school sweetheart Genevieve in 1943, and
they had two sons.
After the war he returned to Long Island, working for a commercial bulb grower until 1950
when he became Superintendent of the Barnes Arboretum in Merion, where he worked
until coming to Swarthmore.
4"h
Dave was instrumental in making and
maintaining the Scott Arboretum we know
today. In honor of his exemplary service to
the Scott Arboretum and Swarthmore
College, we name this the Dave Melrose
Headhouse as we complete payment of the
Wister Center, December 2013. We want
his traits–honorable, humble, humorous,
hard-working, thrifty–to inhabit this place
as much as he held this place in his heart.
R. Robert
Director’s Corner
2013, contributing over $58,000
towards the Wister Center. I am
grateful to all of you both for your
participation and generosity. I want
you to share the sense of accomplishment and pride I feel when I
think about how this building has
transformed our educational programs and special events, our ability
to serve our broad community with
gorgeous activity spaces, and to
provide for many basic Arboretum
needs from tool storage, to a flower
arranger station, to volunteer lockers, to a propagation house, to ADA
3.0"h
compliant restrooms. The Wister
Center still holds the “high water
mark” in terms of sensitive building
Josh Coceano and Marge Firn
with environmental impact in
in action in the Dave Melrose
mind. It is the only Gold Level
Headhouse
LEED (Leadership in Energy and
Environmental Design) certified
building on campus.
The Headhouse will henceforth be known as the Dave Melrose
Headhouse in honor of this milestone and in honor of the decades of service
Dave gave to the Scott Arboretum. The plaque pictured here now graces the
wall at the entrance to the Melrose Headhouse.
Although the building opened in November 2009 and we have been
using it daily since then for all kinds of events and programs (it has become
one of the most popular buildings for other departments of the College to
use), I now have a sense of calm that comes with “burning the mortgage.” We
will now commence work on one more dedication plaque to add to the building, a plaque to recognize and honor all the donors who together made it possible for us to create the Wister Education Center and Greenhouse.
7.5"h
Dave Melrose (front right), Superintendent of Grounds,
with his staff (1984)
Claire Sawyers
Director
Gardens to Visit
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Planning a spring or summer trip and want to find out which gardens to see? While the internet is a great resource for information, the
Scott Horticultural Library also has a fantastic collection of brochures and information from gardens around the country in the “Gardens
to Visit File,” organized by state. Upon returning from trips to places like Lotusland in Montecito, California, to local Delaware Valley
treasures, Scott Arboretum members, volunteers, and staff members have been adding to these files for years. Start here to get ideas for
your next excursion!
Photos: J. Coceano
Tillandsias!
Julie Jenney
amount of white fuzz on the leaves (or trichomes – foliar hairs that
act as a shield); a reduction in leaf and root development; keeping
themselves small with few flowers and fruits per plant; and have a
tendency toward self-fertilization. Tillandsias are very adaptable and
have evolved to be stress tolerant through the mechanisms above and
the fact that they grow extremely slow.
The tillandsias I have range in size from about 1-inch in diameter
to about 10 inches in diameter. They all have stiff, spiky or curling,
glaucous gray leaves. The Tillandsia with stiff leaves are xerophytes
(meaning they grow in dry climates) and those with soft leaves are
referred to as mesic and originate in rainforests. The xeric types are
more commonly found for sale here, such as Tillandsia fraseri and T.
multiflora. Their rosette shapes are formed by their leaves arising from
a single point in the center of the plant. This helps the plant retain
water since it forms a well among the leaf axils. T. caput-medusae
and T. butzii look other wordly – both reminiscent of the snake-filled
head of Medusa. The trichomes of xeric Tillandsia are very highly
developed – when they get moisture on them they are able to transfer
water rapidly from the leaf surface to elongated storage cells inside. As
many gardeners know, the gray, downy characteristic of certain plants
also reflects excessive sunlight.
Tillansdsia usenoides artfully draped from Cornus
mas in the Terry Shane Teaching garden last summer.
Between the last two Unusual Tropicals and Annuals Sales at
the Scott Arboretum I have bought nine tillandsias and I love them!
They are an unusual and creative addition to my garden and my
apartment – and I have found I can successfully grow them inside
during the winter with minimal attention (all nine are alive and
thriving). Tillandsias have become popular as they can be grown in
all kinds of fun ways: perched on wood, in a glass jar, hanging from
tiny moss-filled baskets – they can hang from just about anything, or
simply be placed on a table for decoration. To be able to pick up a
plant in its entirety (roots and all) and hold it in the palm of my hand,
is just one of the reasons I have come to love these strange, little
plants. Here I will share with you how to better understand this odd
but wonderful genus and how to successfully grow these air plants in
your home and spring-summer gardens.
Tillandsias are part of Bromeliaceae. The bromeliad family
includes a wide range of plants such as pineapple (Ananas comosus)
and Spanish moss (Tillandsia usenoides) – did you get to see the
Spanish moss creatively draped by Horticulturist Josh Coceano
on the Cornus mas in the Terry
Shane Teaching Garden this past
summer? With the exception of
some of the southern parts of the
US, all tillandsias come from
Latin America and most grow
best in arid environments. In
their natural habitat they can be
found perched as epiphytes on
trees, bushes, rock outcroppings,
cliffs, or cacti. They are true
air plants and are able to grow
without soil through a variety of
strategies: good water holding
capacity through thick layers of
water storage tissue; an increased
The silver foliage of a large xeric type of Tillandsia
combines beautifully with the annual vine, Cissus
discolor.
Josh Coceano creatively
combined tiny xeric tillandsias
together and hung them like
ornaments outside of the Scott
Arboretum offices.
Another benefit of Tillandsia is the colorful, almost unreallooking blooms. They come in rich purples and reds, pinks, yellows,
and greens. The ones I have at home have stayed green (perhaps due
to reduced light), but the green floral spikes still delight me. The
blooming cycle for some is a couple of weeks, but mine last for many
months and some up to a year. During or after blooming they produce
“pups” or baby Tillandsia, from the base or sometimes from the
inflorescence. While the flowers can be beautiful, I like these plants
for their personality-filled foliage and the fact that they don’t need a
pot.
So, how to best grow these bizarre creatures? From May through
October (or even November, depending on temperatures) they can
be placed outside and put just about anywhere they will receive light
and some moisture. They flourish in our humid summers. During the
growing season, I have a few in tiny wire baskets lined with moss and
hang them from a wall. Some dangle from beneath the fire escape
steps, and one is simply put on a table as an elegant centerpiece. When
I water my pots I spray my Tillandsia with the hose and when they are
outside I don’t fertilize them.
When the temperatures start dipping in the fall (getting close to
32 degrees Fahrenheit), I bring my Tillandsia inside. I have a chain
hanging in my kitchen window where I have them dangling over
con’t on page 4
3
Curator’s Choice
Andrew Bunting
Rhododendron ‘Scintillation’
In the world of rhododendrons there are seemingly
endless choices. The Delaware Valley has the nearly perfect
climate and soil types to grow and display evergreen
rhododendrons. One of my favorites is a Dexter hybrid,
Rhododendron ‘Scintillation’. This large stature
rhododendron can reach 15 feet tall with an equal
spread. In May, many funnel-shaped flowers are
borne in a large ball-shaped truss or flower head.
Each truss will have 11 to 15 flowers which
are 2 ½ inches across and are a vibrant purplepink with yellowish markings in the throat.
This is one of the hardiest of the evergreen
rhododendrons, surviving temperatures as low
as 15 degrees Fahrenheit.
This iconic plant was a selection made
by the Dexter Study Committee,
assembled by Clement
G. Bowers whose
charge was
to bring
together
an informal group to identify
promising rhododendron hybrid seedlings
still found on the former Sandwich,
Massachusetts estate of famed Rhododendron
hybridizer, Charles Dexter from 1945-1953. The
Study Committee included our first director,
John Wister, as well as Henry Skinner (Morris
Arboretum), Paul Vossberg (Westbury
Rose Company), Donald Wyman (Arnold
Arboretum), and rhododendron hybridizers
Edmond Amateis and David Leach.
Dexter seedlings were distributed to over 25 individuals
and institutions including the New York Botanical Garden,
Morris Arboretum, Scott Horticultural Foundation (now the
Scott Arboretum), Tyler Arboretum, Mrs. Arthur Hoyt Scott,
Arnold Arboretum, US National Arboretum, and Biltmore
Gardens, to name a few.
The first visit by the committee was in May of 1949 to the
New York Botanical Garden. Among the Dexter seedlings they
spotted an outstanding pink selection which had a New York
Botanical Garden label reading “#67”. The group re-labeled
this selection as “New York #1”. In all, 16
plants were numbered and ultimately several
cultivars were named including ‘Betty Hume’,
‘Champagne’, ‘Dexter Purple’, ‘Fordham’,
and ‘Tom Everitt’. Paul Vossberg re-named
“New York #1” and called it ‘Scintillation’
and it was introduced by the Westbury
Rose Company in 1957. In Hybrids
and Hybridizers – Rhododendrons
and Azaleas for Eastern North America
Wister states, “It is almost certainly the
finest and best known of all the Dexter
varieties.”
Today, Rhododendron ‘Scintillation’
is a popular landscape rhododendron. At the
Scott Arboretum our best looking specimen
is planted in the Wister Garden at 735 Harvard
Avenue above the wall in the front yard. We also
have some younger specimens planted around the
Amphitheater. This rhododendron thrives in our
acidic soils high in organic matter. It will grow
best in partial shade, but can take considerable
sun as long as there is reasonable moisture during
periods of drought.
Rare Find Nursery promotes an interesting seedling of
‘Scintillation’ called ‘Gem Gardens Scintillation’ which was
selected by Dr. Gustav Melquist and is slightly larger in stature;
it can thrive as far north as Storrs, Connecticut (just northeast of
Hartford) and has deeper pink flowers.
In the garden, rhododendrons are perfect as a backdrop
for smaller evergreen and deciduous shrubs and herbaceous
perennials and make a perfect addition to a woodland garden.
Tillandsias! con’t from page 3
4
potted plants – gathering the little bit of humidity those potted
plants give off. They can also go in a well-lit bathroom where,
like orchids, they benefit from the humidity from the shower. The
biggest Tillandsia I have is hanging from a wire pot hanger in my
bedroom window, again, placed near groupings of potted plants
which give off small amounts of humidity. I mist my plants every
morning, and about once a week I either run my Tillandsia under
the faucet or dunk them in lightly fertilized water (again, like
orchids, they prefer a high nitrogen fertilizer, i.e. 30:10:10). The
xeric types can remain in the water overnight and this allows them
to soak up needed moisture. Misting helps with the humidity but it
is not really “watering” them. Among my potted plants I also have
small decorative bowls that I fill with water to help them survive
the warm, dry air of my apartment during the winter. Washing off
Tillandsia in the sink helps keep pests at bay. With no misting or
rinsing, they are likely to get spider mites. So while they are very
easy to care for, they can’t be neglected. If rot develops from too
much moisture, gently pull the rotted leaves from the center. If
they easily come out continue, but don’t continue if they resist.
Then let the plant completely dry out. If the base becomes soft and
mushy, take a clean knife and cut out all of the bruise and keep
it dry until it callouses over. But the too-much water or rotting
problem shouldn’t happen if they are receiving enough airflow and
light.
There is an informative booklet by Paul T. Isley III called
Genus Tillandsia, The World’s Most Unusual Air Plants, my source
for much of the information in this article. The best thing to do
though, is to come to the Unusual Tropicals and Annuals Sale
to see the many Tillandsia we’ll have for sale, and seek out a
Plant Expert to tell you more about these decorative, fun, and
fascinating plants!
Iris cristata
In the woodland garden, massing or groundcovering perennials play an important role. But it is
also important to have perennials which fill the spaces
between the clumping and single specimen perennials.
Plants like barrenwort (Epimedium), Chinese wild
ginger (Asarum splendens), wild ginger (Asarum
europaeum), foamflower (Tiarella cordifolia), green
and gold (Chrysogonum
virginianum), and the
dwarf crested iris (Iris
cristata) can all fill this
role in the garden.
Iris cristata is a beautiful
woodland iris native from
Pennsylvania south to Georgia
and west to Oklahoma, Missouri,
and Illinois. In its native habitats
it typically grows on rocky wooded slopes
and bluffs. In the garden it will grow best in part
shade but can tolerate both deeper shade and sun.
In full sun it will require supplemental irrigation
during periods of drought. This stoloniferous
perennial has rhizomes like other Iris species
which produces quickly expanding masses in a short
amount of time. Encouraging Iris cristata to spread
in the garden is an easy practice – in early spring as
the leaves are emerging simply tease out pieces of the
rhizome with a couple of leaves and transplant them
elsewhere in the garden.
The flowers of the crested iris look like miniature
versions of the garden iris or bearded iris. There are
different color forms including white, lilac, lavender, or the
pale blue form which is typically found in nature. The flower
configuration is also like that of other iris flowers. In the
center there are three upright pale blue petals or “standards.”
Bending downwards are three more petal-like appendages
called sepals or “falls.” The falls are splotched with golden-
yellow in the center, and white frames the yellow splotch.
The flowers are 3 inches across and stand about 3 to 5
inches tall. Each flower stalk has one to two flowers
borne in late April to mid-May.
The sword-like leaves
are up to 6 inches long. While
most gardeners will covet this
plant for its exquisite flowers, the
foliage offers an interesting textural quality in
the garden. The narrow arching leaves combine
nicely with the bolder foliage of plants like
Hosta, Ligularia, Rodgersia, and Begonia
grandis.
As is true with other great garden
plants, there have been
selections made of Iris
cristata. ‘Powder Blue
Giant’ is a more robust and
vigorous form with soft blue
flowers. ‘Tennessee White’
is a striking cultivar with
alabaster-white flowers and a
slight yellow patch on the falls.
‘Eco Blue Bird’ is a selection made
by Don Jacobs of Eco Gardens which is
a compact blue form. ‘Dick Redfield’ is a
highly coveted form with six versus the typical
three falls. The petals are soft lavender while the
falls are a striking royal purple. The yellow crested
falls have a frilly edge of white. This clone is also more
compact than others.
At the Arboretum we have multiple plantings
of Iris cristata. In the Terry Shane Teaching Garden
we have a white form called ‘Alba’. There are also
plantings at north Kohlberg and in the Glade Garden
where it grows among other native perennials.
Be sure to check out the selection of tillandsias at
this year’s Unusual Tropicals and Annuals Sale!
Spring Plant Sales at the Scott Arboretum
Members Plant Exchange and Sale
Saturday, May 10, 10 am – noon, Wister Center
See brochure for details
Unusual Tropicals and Annuals Sale
Friday, May 16
Preview Party 5:30 – 7:30 pm
$40 per person, tickets required
Saturday, May 17
Member Shopping, 10 am – noon
Public Shopping, noon – 3 pm
Wister Center
J. Coceano
5
J. Coceano
The annual border featured Ensete
(Abyssinian banana) and Colocasia in 2012.
Design and History behind the
Terry Shane Teaching Garden
The reflecting pool in the
shade of Cornus mas
Who was Terry Shane?
Terry Shane was the first chair of the
Associates of the Scott Arboretum and lived
and gardened with her husband, Joseph, in the
Cunningham house. Joseph graduated from
Swarthmore College in 1925 and served the college
as vice president for alumni affairs and public relations for more than 21 years. He was also a key person in the beginning of the Associates of the Scott
Arboretum. Joseph wrote to 40 Swarthmore alumni
asking for a contribution of $100 each to start the
organization and all 40 alumni sent in their contribution, leading to the formation of the Associates
of the Scott Arboretum in 1972. Terry and Joseph’s
son, J. Lawrence “Larry” Shane, graduated from
Swarthmore College in 1956 and filled positions on
multiple committees on the Board of Managers of
the College as well as serving as the Board’s vice
chair in 1977 and as its chair from 1997 through
2003. Their son J. Buckley “Buck” Shane is also a
graduate of Swarthmore College (’50), and created
the Joseph B. Shane ’25 and J. Lawrence Shane ’56
Endowment. Additionally, the Joseph Shane Award
is given to a Swarthmore alum who, over an extended period of time, has contributed both time and
service to significantly benefit the College. Terry
Shane lived to be 104 years old and her passion for
gardening was unwavering, even in her later years.
6
History and Design
Before the Teaching Garden was installed, the
space it now occupies was a simple backyard garden, which Terry Shane cultivated during her time
Mackenzie Fochs
R. Robert
The Terry Shane Teaching Garden, one of the showcase gardens of the
Scott Arboretum, is located just behind the Arboretum offices which are in the
Cunningham House. The house is adjacent to the intersection of College Avenue and
Cedar Lane and the garden tucked behind it is filled with seasons of interest and an
evolving history.
J. Coceano
living in the Cunningham house. At the garden’s dedication ceremony, she recalled the wildflower garden she had put in years before:
“I brought hepatica, wind-flowers, and dogtooth violets from our
Pocono cottage; tiny red columbine from along the Hudson; bluebells from along the Brandywine; bloodroot from where the Frorer
Holly Collection is now; and maidenhair fern from the Pittengers’
Oxford farm.”
The Terry Shane Teaching Garden was constructed in 1989
to celebrate the 60th anniversary of the Arboretum. The design,
created by Rodney Robinson, included a terrace, an arbor, a small
reflecting pool, and beds and borders, all of which can still be seen
in the garden today. The intent of the design was to create an outdoor “room,” or extension of the Cunningham house, and a space
to display select perennial plants. The cedar arbor and an Ilex opaca
(American holly) behind it were included to screen the garden, adding to the feeling of being in an outdoor room. The reflecting pool
area was designed as a more intimate space; indeed, you will often
see visitors reading or having lunch around the pool in nice weather.
There are five dedicated benches throughout the Terry Shane
Teaching Garden for visitors to take pause and enjoy the tranquility
and beauty of the garden.
Purple-colored foliage was the overarching theme for the
garden, and original plantings included Cercis canadensis ‘Forest
Pansy’, Berberis thunbergii ‘Crimson Pygmy’, and two Acer palmatum ‘Crimson Queen’. The Cercis canadensis ‘Forest Pansy’ next to
the reflecting pool is now 14 feet tall. The Acer palmatum ‘Crimson
Queen’ trees were planted in raised beds flanking the entrance to
the formal lawn area; one is an original, and the other was most
recently replaced in 2005. The Berberis thunbergii ‘Crimson Pygmy’
shrubs were replaced in 1998 with a hedge of Taxus × media
‘Hicksii’ (Hick’s yew) to create a more defined space. Curator
Andrew Bunting says this garden has evolved nicely over time; the
Garden Accents
A variety of garden accents have been added since the inception of the garden. Mina, a sculpture by Lydia Leavitt, was donated by The Associates of the Scott Arboretum to commemorate the
25th anniversary of the Associates in 1996. This piece shrouds
the practical function of circulating water in the pond with an
enchanting statuette and adds the soothing sound of trickling
water in the garden.
The stone fence post was salvaged from the lot on Elm
Avenue where the Book and Key Society’s clubhouse, once
stood. According to the Friends Historical Library of Swarthmore
College, “Book and Key was a Swarthmore College men’s secret
honor society established circa 1906 and modeled after the secret
societies at Yale University.”
The mill stone was acquired from an antique dealer near
Gap, Pennsylvania.
J. Coceano
R. Robert
Mina by Lydia Leavitt
beds surrounding the formal lawn space, originally planted with
perennials, are now planted with seasonal annual plants to create a
sense of change from year to year.
Several plant specimens predate the formal design of the
garden, including the Cladrastis kentukea (American yellowwood)
near the Wister Center, the Quercus macrocarpa (bur oak) and
two Ilex opaca (American holly) at the back of the garden, and
the Ulmus americana (American elm) behind the garden. Both the
Pieris japonica (Japanese pieris) and Cornus florida (flowering
dogwood) at the back of the house also predate the Terry Shane
Teaching Garden.
The European purple beech (class tree of 1881) was a significant presence in the garden until January 2014 when it was
removed. In decline for several years, it had become a potential
safety hazard. While this impressive tree will be greatly missed,
the open space now provides an opportunity for the continued
evolution of the Terry Shane Teaching Garden.
The Terry Shane Teaching
Garden after an April shower
Stone fence post (with Tillandsia
usenoides) salvaged from the Book
and Key Society’s clubhouse
7
Crocus vernus ‘Pickwick’
PAID
MEDIA, PA
PERMIT NO. 695
Scott Arboretum Staff
Administrative Coordinator – Jacqueline West
Curator – Andrew Bunting
Director – Claire Sawyers
Educational Programs Coordinator – Julie Jenney
Education Intern – Mackenzie Fochs
Horticulture Coordinator – Jeff Jabco
Horticulturist – Josh Coceano
PR and Volunteer Programs Coordinator – Becky Robert
Special Projects Coordinator – Jody Downer
©2014 Associates of the Scott Arboretum
The Hybrid is published quarterly by:
Associates of the Scott Arboretum
Swarthmore College
500 College Avenue
Swarthmore, PA 19081
610-328-8025
Email: scott@swarthmore.edu
R. Robert
Designed by k.t.d. Design, www.ktddesign.net
©2013 Associates of the Scott Arboretum
www.scottarboretum.org
• Check plants for winter damage and prune out the dead wood. As new growth
starts, it is easy to see where dieback has occurred and where you should
remove it.
• Check trees that were staked last year to see if supports should be removed
or adjusted.
• Look for areas where spring bulbs can be used. Take note and plan to fill
spaces this fall.
• Divide perennials and bulbs where needed.
• Cut back plants that were left for winter interest. Last year’s weather-worn
evergreen foliage (of liriope, hellebores, ferns, epimediums, etc.) should be
removed to improve appearance and to show off flowers. Ornamental grasses
are cut back before new growth starts.
• Rejuvenate mature shrubs by pruning out 1/3 of old wood.
• Prune shrubs that bloom on new wood (i.e. Buddleja, Callicarpa, Caryopteris,
Hydrangea).
• Cut back roses before new growth starts.
• Cut back shrubby dogwoods and willow to encourage new, colorful growth.
• Clean out beds and freshly edge them.
• Prepare new beds (rototill) for planting.
• Add new plants to the garden.
• Harvest your compost pile.
• Mulch beds.
• Aerate lawn areas to relieve soil compaction.
• Plant grass seed in bare lawn spots.
• Check tools and equipment to make sure everything is ready to go (especially
lawn mowers).
• Check hoses and sprinklers.
• Consider putting up fencing or wire around young trees to protect from
nibbling rabbits.
• Start sowing seeds for vegetable and annual flower gardens.
• Check supplies for staking and supporting perennials.
• Cut back overgrown climbers to renovate, such as honeysuckle.
• Pot up summer tropicals such as cannas and dahlias to get started indoors.
• Continue to dig out weeds (especially winter weeds) to limit their seeding
around.
• If time allows, deadhead spent flowers on spring bulbs.
HYBRID
Spring is a busy time in the garden. Here are some of the tasks gardeners of the
Scott Arboretum are doing (and that you can do) in early spring to get ready:
THE SCOTT ARBORETUM OF SWARTHMORE COLLEGE
Chuck Hinkle and Dale Nemec
NONPROFIT ORG.
U.S. POSTAGE
Getting Ready for Spring